Physics in Canada La Physique au Canada

Transcription

Vol. 64 No. 1
Physics in Canada
La Physique au Canada
JANUARY-MARCH (WINTER) 2008
JANVIER À MARS (HIVER) 2008
FEATURING :
Serving the Canadian
physics community
since 1945 /
Servont la communauté
de physique
depuis 1945
Pure Physics, Interdisciplinarity, Multidisciplinarity / Physique pure, interdisciplinarité,
pluridisciplinarité
A Photonics Path to Structural Monitoring
Observations of Total Internal Reflection at a Natural Super-Hydrophobic Surface
Giant Magnetoresistance and its Impact on the Magnetic Recording Industry
PhD Physics Degrees Awarded in Canadian Universities (December 2006 to November 2007)
Doctorats en physique décernés aux universités canadiennes (décembre 2006 à novembre 2007)
Canadian Association
of Physicists /
Association canadienne
des physiciens et
physiciennes
www.cap.ca
jan08-to-trigraphic.qxp
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Page i
PHYSICS IN CANADA
LA PHYSIQUE AU CANADA
Canadian Association
of Physicists
Association canadienne des
physiciens et physiciennes
www.cap.ca
Vol. 63 No. 4 (October-December 2007 / octobre à décembre 2007)
1
Editorial - “Pure Physics, Interdisciplinarity, Multidisciplinarity”,
by B. Jóos, P.Phys., Editor
3
Éditorial - “Physique pure, interdisciplinarité, pluridisciplinarité”,
par B. Jóos, phys., Rédacteur
DE FOND
ARTICLES
DEPARTMENTS
DÉPARTEMENTS
FEATURES
7
Observations of Total Internal Reflection at a Natural SuperHydrophobic Surface, by Lorne Whitehead, Michèle Mossman, and
Alexander Kushnir
13
19
A Photonics Path to Structural Monitoring, by Fabien Ravet and Xiaoyi Bao
24
Photon Production from Relativistic Heavy Ion Collisions,
Giant Magnetoresistance and its Impact on the Magnetic Recording
Industry, by Mark Johnson
by Simon Turbide
5
6
18
Letters / Lettres
27
PhD Degrees Awarded in Canadian
Universities (December 2006 to November 2007) /
Doctorats décernés aux universités canadiennes
(décembre 2006 à novembre 2007)
Cover / Couverture :
News / Information
Departmental, Sustaining, and
Corporate-Institutional Members /
Membres départementaux, de
soutien, et corporatifs-institutionnels
Advertising Rates and Specifications (effective January 2008) can be found on the PiC website
(www.cap.ca - Physics in Canada).
Picture of the Confederation Bridge
in Borden-Carleton, P.E.I. uploaded
on
Outdoors
Webshots
by
“dianeaub” in album “Scenes of
Prince Edward Island” on Aug. 25,
2007 (found through search on
Google Images). The bridge is discussed in the article on Structural
Monitoring by F. Ravet and X. Bao.
Photographie du Pont de la
Confédération à Borden-Carleton.
Ile du Prince-Edouard, mis sur
Outdoors Webshots par « dianaaub »
dans l’album « Scènes de l’Ile du
Prince Edouard le 25 août 2007
(trouvé utilisant Images Googles).
Le pont est discuté dans l’article
Structural Monitoring par F. Ravet et
X. Bao.
Les tarifs publicitaires et dimensions (en vigueur depuis janvier 2008) se trouvent sur le site internet de
La Physique au Canada (www.cap.ca - La Physique au Canada).
LA PHYSIQUE AU CANADA / Vol. 64, No. 1 ( jan. à mars (hiver) 2008 ) C i
DEPARTMENTS
DÉPARTEMENTS
31
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2008 CAP Congress / Congrès de l’ACP
2008
- Highlights / Points d’intêréts
- Herzberg Public Lecture / Conférencier
Herzberg
- Invited Speakers / Conférenciers
invités
PHYSICS IN CANADA
LA PHYSIQUE AU CANADA
The Journal of the Canadian Association of
Physicists
La revue de l'Association canadienne des physiciens et physiciennes
ISSN 0031-9147
EDITORIAL BOARD / COMITÉ DE RÉDACTION
Editor / Rédacteur
Béla Joós, PPhys
37
37
Books Received / Livres reçus
Book Reviews / Critiques de livres
Back
Cover Employment ad / Poste d’emplois
Physics Department, University of Ottawa
150 Louis Pasteur Avenue
Ottawa, Ontario K1N 6N5
(613) 562-5758; Fax:(613) 562-5190
e-mail: [email protected]
Associate Editor / Rédactrice associée
Managing / Administration
Francine M. Ford
c/o CAP/ACP
Book Review Editor / Rédacteur à la critique de livres
Richard Hodgson, PPhys
c/o CAP / ACP
Suite.Bur. 112, Imm. McDonald Bldg., Univ. of / d' Ottawa,
150 Louis Pasteur, Ottawa, Ontario K1N 6N5
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Board Members / Membres du comité :
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Département de physique, de génie physique et d’optique
Université Laval
Cité Universitaire, Québec G1K 7P4
(418) 656-2655; Fax: (418) 656-2040
David J. Lockwood, PPhys
Institute for Microstructural Sciences
National Research Council (M-36)
Montreal Rd., Ottawa, Ontario K1A 0R6
(613) 993-9614; Fax: (613) 993-6486
Tapash Chakraborty
Canadian Association of Physicists (CAP)
Association canadienne des physiciens et physiciennes (ACP)
The Canadian Association of Physicists was founded in 1945 as a non-profit association
representing the interests of Canadian physicists. The CAP is a broadly-based national
network of physicists in working in Canadian educational, industrial, and research settings. We are a strong and effective advocacy group for support of, and excellence in,
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L'Association canadienne des physiciens et physiciennes a été fondée en 1946 comme
une association à but non-lucratif représentant les intérêts des physicien(ne)s
canadien(ne)s. L’ACP est un vaste regroupement de physiciens oeuvrant dans les
milieux canadiens de l'éducation, de l'industrie et de la recherche. Nous constituons un
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http://www.cap.ca. Les formulaires d’adhésion sont aussi disponibles dans la rubrique
“Adhésion” sur ce site.
II
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CANADA / VOL. 64, NO. 1 ( Jan.-Mar. (Winter) 2008 )
Canada Research Chair Professor, Dept. of Physics and Astronomy
University of Manitoba, 223 Allen Building
Winnipeg, Manitoba R3T 2N2
(204) 474-7041; Fax: (204) 474-7622
Michael Steinitz, PPhys
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Page 1
ÉDITORIAL
PURE PHYSICS, INTERDISCIPLINARITY, MULTIDISCIPLINARITY
PHYSIQUE PURE, INTERDISCIPLINARITÉ, PLURIDISCIPLINARITÉ
P
ure physics : the term implies a value system, a
certain ideal for our discipline. The word “pure”,
as in the social context in which it is sometimes
used, reflects an attachment to a restrictive definition that could have a limiting effect on the discipline were
it adhered to with excessive zeal. Many of us were trained
in departments that focussed primarily on nuclear physics,
particle physics and condensed matter physics. However,
for some time now, there have been departments with
long-standing traditions in astronomy, optical physics,
plasma physics, medical physics, and, more recently, biophysics.
After years of stability, however, the world of science is in
a state of high fluctuation. Many departments are being
impacted by a scientific environment where the delineation between disciplines is fading, creating opportunities for physics to play a new, more extroverted role. It has
often been said that physics “is the gateway to multiple
career options” (quoted from the APS Careers in Physics
poster). This reflects the reality that training in physics
may lead to many other scientific or engineering disciplines, and that skills acquired in physics, especially problem-solving techniques, enable students to succeed in a
number of professions. “Physicists” have been described
as members of a “hidden” profession [1]. We rarely find a
job description within industry asking for a physicist.
With science quickly becoming multidisciplinary and new
interdisciplinary fields appearing, it is the opportune time
to rethink the role of physics in scientific training. Should
physics departments continue to focus on a training base
in pure physics and send their graduates out into the labour
market to make contributions to the success of scientific
activities, even receiving Nobel prizes in other disciplines,
or should they take a more aggressive stance by offering
more specific specializations? To state that physics
departments are concentrating exclusively on basic
physics training is an oversimplification. We have a long
tradition of having areas of applied physics associated
with physics departments, notably astronomy, medical
physics, oceanography, planetary science and geophysics;
but that is more the exception than the rule.
During the last decade a number of factors have changed
the dynamics within universities, with increasing pressure
on physics departments to find new ways of maintaining
their discipline’s lead position. Given administrations that
increasingly evaluate departments using yardsticks related
exclusively to cost and revenue, new ways have to be
found to boost enrolment at all levels. Physics is evolving,
dealing with exciting topics at the forefront of knowledge
generation : quantum information and quantum computing
(covered in the last issue of PiC-PaC), ultrashort laser
pulses (from femtoseconds to attoseconds), the grand unification of forces (there are some worries, however, about
the direction this discipline is taking [2] ), cosmology,
astrophysics, high-Tc superconductors and other N-body
phenomena, nanophysics and molecular devices, nonlinear systems, atomic manipulation of biological molecules
– the list is far from complete, but it is nonetheless impressive. In fact, the emergence of several of those fields has
had a positive impact on many physics departments, and
I see a renewed enthusiasm for physics research. That may
be enough to maintain physics departments at their current
size, but they could probably do better if they made efforts
to attract students who did not traditionally choose
physics. Many scientific disciplines are maturing, and they
must develop quantitative models based on the laws of
physics, which requires knowledge not normally taught as
part of their discipline. Finally, in looking at science as a
whole, many subjects that are currently considered to be in
the forefront, such as nanoscience and life sciences,
require skills that are not associated with a single discipline.
Such developments provide physics departments with
opportunities to widen their influence by establishing
innovative programs that increase the potential student
pool. These programs can take a variety of forms, such as
an option within existing programs of specialization, separate after the first year of the existing program, or in combination with other departments using an interdisciplinary
approach.
To get an idea of how Canadian physics departments are
coping with these new issues, in November 2007 I sent out
a short questionnaire to the Heads/Chairs of the various
physics departments (unfortunately in English only), asking what their departmental policy was on the non-traditional physics disciplines, whether they were hiring professors in those non-traditional disciplines and in what
The contents of this journal, including the views expressed above, do not necessarily represent the
views or policies of the Canadian Association of Physicists. Le contenu de cette revue, ainsi que les
opinions exprimées ci-dessus, ne représentent pas nécessairement les opinions et les politiques de
l’Association canadienne des physiciens et des physiciennes.
Béla Joós is a
Professor of Physics
at the University of
Ottawa. He has
been a member of
the Editorial Board of
Physics in Canada
since January 1985
and took over as
Editor in June 2006.
Béla Joós est professeur de physique
à l’Université
d’Ottawa. Il est
membre de Comité
de rédaction de la
Physique au Canada
depuis 1985, et est
devenu rédacteur en
juin 2006.
LA PHYSIQUE AU CANADA / Vol. 64, No. 1 ( jan. à mars (hiver) 2008 ) C 1
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EDITORIAL
types of positions (e.g. multiple assignments), and whether
they were making changes to their first-year programs to prepare students for those non-traditional areas. I received information from 16 departments, ranging from the smallest to the
largest and from coast to coast, enough to get a reasonable picture of the overall situation.
First of all, departments have to make tough choices on the
direction their research is going to take, which generally
reflects the pressures the universities themselves are facing.
For example, to benefit from the Canada Research Chairs program and to obtain grants from the Canadian Foundation for
Innovation, universities have had to realign their priorities for
research, forcing their departments to do the same. In addition,
a critical mass of researchers in each field of research undertaken by the university is increasingly needed to succeed in securing research funding and student enrolment. Without that critical mass, it is difficult to acquire major equipment or offer an
interesting selection of courses. All of this means that, in the
medium-sized departments in particular, we find only a few
priority areas. If a department has a strong reputation in a traditional sub-discipline, it will be difficult for them to move into
a new discipline that is radically different. Circumstances must
be suitable for expanding into new research areas, especially
as, in many cases, there is reluctance on the part of the academic staff.
As I said, some departments already have a significant commitment to what we call “applied physics”, such as astronomy,
optics, medical physics and oceanography. The issue here is
whether these departments have recently changed their strategy regarding the development of their programs. We are seeing
the emergence of new disciplines within the physics envelope,
such as quantum information, quantum materials, the science
of short-pulse electromagnetism, physics education, etc. Of
equal importance is the rebirth of astrophysics. The first three
are essentially physics disciplines with multidisciplinary components that provide opportunities for cooperation with other
disciplines, most notably chemistry and engineering. Physics
education is a new program, with its own challenges. It has
been generally recognized that this subject is of growing
importance in ensuring not only the success of physics as an
academic discipline, but in the wider context of the scientific
culture. Nevertheless, the absence of funding sources may
explain why many departments hesitate to hire researchers in
this field [3]. In spite of all this, its visibility is slowly growing.
We are all aware of the arrival of Nobel laureate Carl Wieman
at UBC to undertake physics education research, and the activities of the CAP’s Division of Physics Education demonstrate
that there is vigorous activity in this area in many universities.
In addition to those disciplines that reflect a natural evolution
of physics, there are new directions that are more strongly multidisciplinary: materials physics, in particular functional nanomaterials, the science of ultrashort pulses, and biological
physics (or the physics of living systems). All these disciplines
lead to closer linkages between departments and to cross-
2 C PHYSICS
IN
appointments, mostly in biological physics. Opportunities to
participate in the advances in life sciences seem important, but
there are administrative barriers in both inter- and multidisciplinary research. These new subjects have led to the creation of
new programs in physics, microelectronics, biophysics, medical physics, environmental physics, and a variety of new
avenues, but we are a long way from programs that directly
involve several departments. At the University of Ottawa, we
are addressing this challenge in two disciplines : photonics and
biological physics. In the first case, we are required to deal
with the difficulty of sharing a program with a professional faculty - Engineering. Although biological physics could involve
medicine, we are developing a new program in cooperation
with Biology.
In conclusion, the expansion of many scientific disciplines will
depend on lowering the administrative barriers between departments and faculties. The first signs that this new era has begun
seem to be visible, but they are still faint. What is encouraging
is that the possibilities for science remain as exciting as ever,
and the analytical approaches favoured by physicists are finding ever-expanding applications.
I would like to thank the chairs who responded to the questionnaire on interdisciplinarity and multidisciplinarity.
Béla Joós, P.Phys.
Editor, Physics in Canada
1.
2.
3.
J.S. Rigden and J.H. Stith, “The Business of Academic
Physics”, Physics Today, Nov. 2003, p. 45.
Lee Smolin, The Trouble with Physics, Houghton Mifflin,
2007.
Open letter to NSERC by Marina Milner-Bolotin,
Department of Physics, Ryerson University, Toronto,
Canada (dated December 3, 2007), Physics in Canada,
this issue, pg. 5 (2008).
Comments of readers on this editorial are more than welcome.
PHYSIQUE PURE, INTERDISCIPLINARITÉ,
PLURIDISCIPLINARITÉ
Physique pure, ce terme évoque une échelle de valeur, un certain idéal de notre discipline. Le qualificatif « pur », dans le
contexte social dans lequel il est parfois utilisé, reflète un
attachement à une définition restreinte qui pourrait limiter le
progrès de la discipline si elle est épousée avec trop de fermeté.
Beaucoup d’entre nous avons été formés dans des départements qui se concentraient sur la physique nucléaire, la
physique des particules, et de la matière condensée primordialement. Cependant, depuis longtemps, il existe des départements avec de longues traditions en astronomie, physique
optique, physique des plasmas, physique médicale, et, plus
récemment biophysique.
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ÉDITORIAL
Cependant, après bien des années de stabilité la situation en
science est en grande effervescence. Beaucoup de départements se voient affectés par un monde scientifique où les barrières entre les disciplines s’estompent et des opportunités s’offrent à la physique de jouer un rôle nouveau, plus tourné vers
l’extérieur. Il a souvent été dit que la physique « est le portail
qui mène vers de multiples options de carrières » (en anglais
l’APS sur son affiche de carrières écrit « Physics is the gateway
to multiple career options »). Cela reflète la réalité qu’une formation en physique peut conduire à beaucoup de disciplines en
science et génie, et les aptitudes acquises dans une formation
en physique, en particulier en techniques de solution de problèmes, permettra à nos étudiants de réussir dans de nombreuses
professions. ‘Physicien’ a aussi été qualifié de profession
cachée [1]. Il est rare de trouver dans une entreprise la profession ‘physicien’ dans la description de postes.
Maintenant que la science devient rapidement pluridisciplinaire et que de nouveaux domaines interdisciplinaires apparaissent, il est opportun de repenser le rôle de la physique dans
la formation scientifique. Les départements de physique
doivent-ils continuer à se concentrer sur une formation de base
en physique pure et envoyer leurs diplômés sur le marché du
travail pour contribuer au succès de diverses activités scientifiques, et même obtenir des prix Nobel dans d’autres disciplines, ou être plus agressifs en offrant une spécialisation plus
spécifique? Affirmer que les départements de physique se concentrent seulement sur la formation de base est d’ailleurs une
simplification. Il y a une longue tradition de domaines de
physique appliquée attachés à certains départements de
physique, notamment l’astronomie, la physique médicale,
l’océanographie, la science planétaire, et la géophysique, mais
c’est plutôt l’exception que la règle.
Durant la dernière décennie un certain nombre de facteurs ont
changé la dynamique dans les universités, et la pression sur les
départements de physique s’accroît afin qu’ils trouvent des
manières innovatrices de maintenir leurs rôles de discipline de
pointe. Avec une administration centrale qui juge de plus en
plus l’importance d’une unité avec des métriques liés aux coûts
et revenus, cela signifie trouver des façons d’augmenter les
inscriptions étudiantes aux différents niveaux. La physique
évolue et traite encore de nombreux sujets excitants à la pointe
de la connaissance : information quantique et calcul quantique
(le sujet du dernier numéro de PiC-PaC), la physique des pulsations lasers ultra-brèves (du femtoseconde à l’attoseconde),
la grande unification des forces (il y a cependant des inquiétudes sur la direction que prend cette discipline [2]), la cosmologie, l’astrophysique, les supraconducteurs à haute-Tc et
autres phénomènes à N corps, la nanophysique et les dispositifs moléculaires, les systèmes non-linéaires, la manipulation
atomique des molécules biologiques…Cette liste n’est pas
complète, mais elle est déjà impressionnante. En fait l’émergence de certains de ces domaines a eu un effet positif sur
plusieurs départements de physique, et je sens un enthousiasme renouvelé pour la recherche en physique. C’est peut-être
suffisant pour maintenir la taille actuelle des départements de
physique, mais ces départements pourraient probablement faire
mieux, en allant chercher une clientèle qui traditionnellement
ne choisissait pas la physique. Un nombre de disciplines scientifiques murissent et doivent développer des modèles quantitatifs basés sur des lois physiques qui exigent des connaissances qui ne font pas partie de la formation habituelle reçue
dans leur domaine. Finalement, en regardant l’ensemble de la
science, plusieurs des sujets qui sont considérés de pointe
aujourd’hui, telles la nanoscience et les sciences de la vie,
requièrent des compétences qui ne sont pas associées à une
seule discipline.
Ces développements offrent aux départements de physique
l’opportunité d’étendre leur champ d’action en établissant des
programmes innovateurs qui accroissent le champ d’étudiants
potentiels. Ces programmes peuvent prendre diverses formes :
une option dans des programmes actuels de spécialisation ou
avec concentration, indépendants dès la première année des
programmes existants, ou conjoints avec d’autres départements
dans le style pluridisciplinaire.
Pour avoir une idée comment les départements de physique au
Canada font face à ces nouvelles questions, j’ai envoyé au mois
de novembre un court questionnaire aux directeurs de départements (malheureusement il n’était qu’en anglais) leur demandant quelle est leur politique départementale concernant les
domaines non-traditionnels de la physique, s’ils engagent des
professeurs dans ces domaines non traditionnels, et dans quels
types de poste (avec affectation multiple par exemple), et s’ils
font des changements à leurs programmes de premier cycle
pour préparer leurs étudiants à ces domaines non-traditionnels.
J’ai de l’information sur seize départements des plus grands
aux plus petits, de l’est à l’ouest, suffisamment pour dresser un
portrait de la situation.
Tout d’abord, les départements doivent faire des choix parfois
difficiles sur leurs directions de recherche qui reflètent les pressions que les universités elles-mêmes subissent. Par exemple,
pour bénéficier des chaires de recherche du Canada et des
fonds de la Fondation canadienne de l’innovation , les universités ont dû établir leurs axes prioritaires de développement de
la recherche, forçant les départements à faire de même. De
plus, une masse critique de chercheurs dans chaque domaine de
recherche est de plus en plus nécessaire pour faciliter le succès
des chercheurs par la levée de fonds et le recrutement d’étudiants. Sans masse critique il est difficile d’obtenir des
équipements majeurs ou d’offrir un choix intéressant de cours.
Tout ceci signifie que dans les départements de taille moyenne
en particulier on ne trouvera que quelques domaines prioritaires. Si un département a une forte réputation dans un
domaine traditionnel, il lui sera difficile de s’embarquer dans
une nouvelle discipline radicalement différente. Il faut des circonstances propices pour l’épanouissement de nouvelles directions de recherche, surtout que dans beaucoup de cas il y a de
la réticence de la part du corps professoral.
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EDITORIAL
Comme je l’ai mentionné plus haut, il y a déjà des départements qui ont un engagement important dans ce que l’on pourrait appeler des disciplines appliquées de la physique, telles que
l’astronomie, l’optique, la physique médicale, et l’océanographie entre autres. Ici, la question que l’on se pose, c’est si les
départements ont changé récemment leur stratégie concernant
le développement de leurs programmes. On voit l’émergence
de nouvelles disciplines dans les confins de la physique telles :
l’information quantique, matériaux quantiques, science des
pulsations électromagnétiques courtes, l’éducation en
physique, etc. Tout aussi importante est la renaissance que connaît l’astrophysique. Les trois premières disciplines sont
essentiellement de la physique, et elles ont des composantes
multidisciplinaires offrant la possibilité de collaborations avec
d’autres disciplines, notamment la chimie et le génie.
L’Education en physique est une nouvelle bête avec ses défis
particuliers. Il y a une reconnaissance générale que le sujet a
une importance croissante pour assurer non seulement le succès de la physique comme discipline académique mais dans un
contexte plus large celui de la culture scientifique. Cependant,
l’absence de sources de financement explique peut-être
pourquoi beaucoup de départements hésitent à y investir du
personnel [3]. Malgré tout, sa visibilité lentement s’accroît.
Nous sommes tous au courant de l’arrivée du Prix Nobel Carl
Wieman à UBC pour la recherche en éducation, et les activités
de la Division en éducation de l’ACP témoignent d’une activité vigoureuse dans plusieurs universités.
physique, physique médicale, physique de l’environnement, et
à une variété de nouveaux cours, mais nous ne sommes pas
encore au stade de programmes qui impliquent directement
plusieurs départements. A l’Université d’Ottawa nous faisons
face à ce défi dans deux disciplines : la photonique et la
physique biologique. Le premier cas fait face à la difficulté de
partager un programme avec une faculté professionnelle, le
Génie. Bien que le deuxième pourrait impliquer la médecine,
nous planifions un nouveau programme en coopération avec la
biologie.
En conclusion, un épanouissement de beaucoup de disciplines
scientifiques va dépendre de la baisse des barrières administratives entre départements et facultés. Les premiers bourgeons de
cette ère nouvelle semblent apparaître mais elles sont encore
timides. Ce qui est encourageant, c’est que les possibilités de la
science demeurent tout aussi excitantes, et les approches analytiques que favorisent les physiciens ont des applications de
plus en plus étendues.
Je remercie les directeurs de départements qui ont répondu à
mon questionnaire sur l’interdisciplinarité et la multidisciplinarité.
Béla Joós, phys.
Rédacteur, La Physique au Canada
1.
En plus de ces disciplines qui reflètent l’évolution naturelle de
la physique, il y a de nouvelles directions plus fortement
pluridisciplinaires : la physique des matériaux, en particulier
les nanomatériaux fonctionnels, la science des pulsations très
brèves, et la physique biologique (ou la physique des systèmes
vivants). Bien que toutes ces disciplines conduisent à des rapprochements entre départements et à des affectations croisées,
ces dernières sont les plus fréquentes pour la physique
biologique. Les opportunités de participer à des avancements
en science de la vie semblent importantes, mais il y a des défis
administratifs à la recherche interdisciplinaire, et pluridisciplinaire. Ces nouveaux sujets ont conduit à la création de nouveaux programmes de physique, en micro-électronique, bio-
2.
3.
J.S. Rigden and J.H. Stith, “The Business of Academic
Physics”, Physics Today, Nov. 2003, p. 45.
Lee Smolin, The Trouble with Physics, Houghton Mifflin,
2007.
Lettre ouverte au CRSNG par Marina Milner-Bolotin
Département de physique, Université Ryerson, Toronto,
Canada (daté le 3 décembre 2007), La Physique au Canada,
ce numéro, pg.5 (2008).
Les commentaires de nos lecteurs au sujet de cet éditorial sont
bienvenus.
NOTE: Le genre masculin n’a été utilisé que pour alléger le
texte.
The Editorial Board welcomes articles from readers suitable for, and
understandable to, any practising or student physicist. Review papers
and contributions of general interest are particularly welcome.
Le comité de rédaction invite les lecteurs à soumettre des articles qui
ntéresseraient et seraient compris par tout physicien, ou physicienne,
et étudiant ou étudiante en physique. Les articles de synthèse sont en
particulier bienvenus.
4 C PHYSICS
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Page 5
LETTRES
LETTERS / LETTRES
Open Letter to
Dr. Suzanne Fortier, President
Natural Sciences and Engineering Research Council of Canada
Can We Afford Not to Fund
Science Education in
Canada?
Marina Milner-Bolotin
Department of Physics, Ryerson University, Toronto, Canada
(December 3, 2007)
Dear Madame President,
The field of science education is instrumental in the success of
any nation, especially a nation which prides itself in its technological achievements. Based on the statement of vision published on the NSERC web site, I understand that the organization you represent has a vision of "making Canada a country of
discoverers and innovators for the benefit of all Canadians". I
presume that this vision implies having high quality science
education for all Canadians. However, science education in
general, and physics education specifically does not officially
exist in Canada as a scientific discipline. At least it does not
exist in the eyes of the Canadian government, which will not
fund it through federal granting agencies like NSERC. This is
troubling, since the refusal to support science education
research by NSERC has significant negative ramifications for
science faculty, teachers, and kindergarten to university students. This is especially troubling, given that faculty whose field
of research is science education, and who are scientists by
training cannot compete for NSERC funds as their science colleagues pursuing more traditional science research. As a result,
science faculty pursuing research in science education receive
very limited support in designing and implementing innovative
curricula, laboratories and modern instructional methods. The
unavailability of NSERC funding for our research is a setback
for our ability to advance high quality science education in
Canada.
A year ago, the University of British Columbia was able to
attract Physics Nobel Laureate, Professor Carl Weiman, by
offering him 12 million dollars to start a Carl Wieman Physics
Education
Initiative
(http://www.cwsei.ubc.ca/
departments/index.html). This initiative opened a new era in
Canadian Science Education, showing that a major Canadian
Research University realizes that in order to improve the quality of science teaching, one has to recognize the field of science
Science education, as a research field, needs to have continuing granting support from NSERC, as the main goal of our
research is to improve the state of science education in
Canada using our science backgrounds, our knowledge of
how people learn science, and of how science should be
taught. I strongly believe that we must recognize the crucial
difference between the responsibilities of administering educational Institutions, which is a provincial responsibility, and
the field of science education research, which is a field of
research that is of national (and international) scope: we are
scientists who have scientific expertise and whose goal is to
scientifically pursue science education as a field of research.
I also strongly believe that the present practice of limiting science education funding to SSHRC puts fundamental limitations on what fields of research we can pursue. Science education does not belong to the social sciences or humanities.
Only part of the science education research fits SSHRC's
mandate. If a researcher is interested in investigating how students understand particular science topics or how science
instruction can be improved, then SSHRC will not be an
appropriate funding agency for this kind of research. The
Canadian Association of Physicists (CAP) has recognized this
problem and recently sent a letter to the presidents of
NSERC, SSHRC and CIHR suggesting a way to improve
the evaluation of research in the field of Science education.
The letter is posted at https://www.cap.ca/news/briefs/
SSHRC.pdf .
LETTRES
I am an Assistant Professor of Physics at Ryerson University, a
theoretical physicist, and a physics educator by training. My
area of research is physics education. I study how students
learn physics and how physics instructors can do a better job of
teaching physics, not only to physics majors, but to every student in our classes. Physics education is a very exciting and
important field of study, especially today, when many of the students taking introductory physics courses are not specifically
interested in physics, but are only taking it because it is a prerequisite or requirement for other courses or programmes.
education research and to invest financial resources in it.
Moreover, it also comes with the acknowledgement that science research expertise does not necessarily mean that a
professor is going to be effective in his/her teaching. However,
this initiative was aimed mainly at the University of British
Columbia and has not yet had a significant effect on the funding of science education initiatives at other Canadian universities.
Based on the level of public interest in the field, which translates into the large number of popular science books and science-related interviews in the media, we all can see that more
and more Canadians now recognize the importance of what
we are doing, even though it is still done without the support
of NSERC, or too often without any support at all from our
government.
When will NSERC recognize that science education has a
legitimate place among other scientific pursuits and that its
impact is crucial, not only at the college or university level, but
also for achieving adequate levels of scientific literacy among
the Canadian public? By comparison, in the United States,
the National Science Foundation and other major agencies
fully support all aspects of work aimed at improving science
education in that country.
Today we have a wonderful opportunity to start supporting
Canadian science education research and efforts to improve
it. We have a physics Nobel Laureate on board who not only
started a world-class science education initiative at UBC, but
also showed that investing in science education (which he did
3/11/2008
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LETTERS
LETTERS
LETTERS / LETTRES (... CONT’D)
with his Nobel Prize money) can bring the
excitement of science to millions of people
all over the world [1]. Today we have a large
number of scientists in Canada who are
interested in science education and are
ready to contribute to the field. These people
want to stay in Canada, rather than pursue
their research elsewhere, but in order to pursue research in the field of their choice they
need to be recognized and supported.
Today, the fields of science, mathematics,
technology, and engineering education are
booming all over the world. The overwhelming success of science educators in Europe,
Asia, Australia and the Americas shows that
investing in science education pays off. We
have an historic opportunity to bring
Canadian science education to the world
level by supporting it with NSERC grants
and showing university administrators that
science education, and faculty involved in it,
are valued and should be supported within
colleges and universities.
I strongly believe that it is now the right time
to act, as it is not yet too late. As a society,
we simply cannot afford not to fund science
education research any more.
Sincerely,
Marina Milner-Bolotin
1. K. Perkins, W. Adams, M. Dubson,
N. Finkelstein, S. Reid, C. Wieman, and
R. LeMaster, The Physics Teacher 44, 18
(2006).
Raising Scientific Literacy
(or Bamboo under my
Fingernails)
Physics in Canada
Vol. 63, No. 3 (July-September 2007)
January 21, 2008
Dear Dr. Joós,
I am delighted to see that you published Mr.
Jay Ingram’s plenary address to CAP’s 2007
Congress (“Raising Scientific Literacy (or
Bamboo under my Fingernails),” Physics in
Canada 63, 3, (July-September 2007)) and
made it freely available. However I am concerned about the absence of references and
6 C PHYSICS
IN
the apparent lack of critical review. Readers
of a scholarly journal such as Physics in
Canada expect the same rigorous standards
to be applied to all articles they read, regardless of content.
A quick examination of the article reveals the
following weaknesses:
1. The first quote by C.P. Snow could be
attributed as follows: C. P. Snow, The
Two Cultures and a Second Look
(Cambridge University Press, New York,
1965), p. 107.
2. The article attributed to Morris Shamos
(p. 110) is not from The Scientist, but
from The Sciences : M. Shamos, The
Sciences 28, 14 (1988), p. 19.
3. The reference to a one-percent increase
in level of understanding stem cells during the 2005 election could be attributed
to Liza Gross (L. Gross, PLoS Biology 4,
680 (2006)).
4. The article attributed to “Paul Bloom in
Science” (p. 111) should read “Paul
Bloom and Deena Skolnick Weisberg”
(P. Bloom and D.S. Weisberg, Science
316, 996 (2007).
5. The article about intuitive physics is by
Michael McCloskey and not Michael
McElroy (M. McCloskey, Scientific
American 248, 122 (1983)).
I have not corrected the reference to the
National Post editorials on global warming,
nor to Jon Miller’s paper delivered at the
AAAS meeting, since I am unsure if it was
“Public Understanding of Science: Are
Europeans Better at it?” (delivered Feb. 15,
2007), or “Civic Scientific Literacy across the
Life Cycle” (delivered Feb. 17, 2007).
Mr. Ingram is a role model for young scientists. Presenting his article in Physics in
Canada surely adds value and prestige to
your publication. However, any article you
publish must maintain the scientific standards of a scholarly work.
Sincerely,
Debbie Chaves
(Ph.D. Biophysics)
Wilfred Laurier University
[email protected]
NEWS
Council appoints
CERN’s next
Director General
On 14 December 2007
CERN Council appointed
Professor Rolf-Dieter
Heuer to succeed
Dr Robert Aymar as
CERN’s Director
General. Professor Heuer
will serve a five-year
term, taking office on
1 January 2009. His mandate will cover the early
years of operation and
first scientific results
from the Laboratory’s
new flagship research
facility, the Large Hadron
Collider (LHC). The
LHC is scheduled to
begin operation in summer 2008.
Currently Research
Director for particle and
astroparticle physics at
Germany’s DESY laboratory in Hamburg, a post
that he took up in 2004,
Professor Heuer is no
stranger to CERN. From
1984 to 1998, he was a
staff member at the
Laboratory, working for
the OPAL collaboration
at the Large Electron
Positron collider (LEP)
research facility. From
1994 to 1998, he was the
collaboration’s
spokesman.
3/11/2008
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ARTICLE DE FOND
OBSERVATIONS OF TOTAL INTERNAL REFLECTION
AT A NATURAL SUPER-HYDROPHOBIC SURFACE
BY
LORNE WHITEHEAD, MICHELE MOSSMAN AND ALEXANDRA KUSHNIR
T
he interaction of fluid drops on surfaces is an
important and well-studied field involving energy
associated with the interfaces between immiscible
materials. This energy is usually called surface
tension, is often represented with the symbol γ, and has
units of N/m (a force per unit length), or equivalently, J/m2
(an energy per unit area). It is well known that fluid interfaces tend to change shape to minimize their surface area
and hence their surface energy [1]. In this paper, we will
focus on a system that involves three distinct materials –
water (in the form of a drop), a solid (forming an adjacent
flat substrate), and air (surrounding both), as shown in
Figure 1. In turn, there are three different surface tensions
that determine the shape of the water drop - that of the surface-water interface (γsw), the water-air interface (γwa),
and the surface-air interface (γsa).
If one ignores gravity, which is relatively unimportant for
small drops, the shape of the surface depends entirely on
the relative magnitudes of the surface tension values and
Fig. 1
Surface tension characteristics determining the shape of
a water drop on a surface.
SUMMARY
It is well known that some plant leaves, most
notably those of the lotus plant, possess
super-hydrophobic properties as a selfcleaning feature as a result of the presence
of microscopically small surface features.
We have recently noted that the leaves of the
arbutus tree exhibit similar properties, and
that when the leaf is immersed in water, the
air trapped within the nanostructures results
in conditions that are favourable for total
internal reflection (TIR), causing the leaf to
appear extremely reflective from some viewing directions. In this paper, we discuss the
basic optical principles behind this natural,
unusual and visually interesting manifestation of the phenomenon of TIR.
is a portion of a sphere. That portion is typically described
by specifying the so-called contact angle, θ, which is the
angle the surface of the drop makes with the solid surface,
measured from the inside of the drop. Young’s Equation [2]
in Equation (1) describes the relationship between the contact angle and the surface tension forces.
cos θ =
γ sa − γ sw
γ wa
(1)
A water drop on PTFE, as an example, typically has a contact angle of roughly 100o [3] and there is a wide range of
values for other materials. Importantly, it is only the
atoms and molecules at the solid surface that determine
the contact angle, so very thin film coatings can profoundly alter the contact angle.
Such behaviour of drops on a surface is important in a
wide range of circumstances. In some situations, for
example in coating applications, it is important that the
water has a very low contact angle so that it easily coats or
“wets” the material. Surfaces that wet easily are often
referred to as hydrophilic. In other cases, such as in waterproof clothing, it is desirable for water to “bead up”; the
term hydrophobic is used to describe surfaces of this type
that tend to repel water even in wet conditions.
For readily available materials, the contact angle on a
smooth hydrophobic surface is generally less than about
120o [4]. However, the angle can be increased quite dramatically by using a rough or structured surface instead of
a smooth one [5]. If the rough surface has the correct size
and distribution of surface features, it can exhibit so-called
super-hydrophobic properties by trapping air voids
between the surface features [6]. This happens because the
intrinsic surface properties of the material results in a contact angle between the water and the material that is sufficiently high that the water cannot flow into the interstitial
regions to displace the air. The drop instead rests only on
the hydrophobic tips of the features, and in order to minimize the total energy in the system, the drop assumes a
much more complete spherical shape, with a contact angle
greater than 150o [7], as shown in Figure 2.
Lorne Whitehead
<lorne.whitehead@
ubc.ca>, Michele
Mossman and
Alexandra Kushnir,
Department of Physics
and Astronomy,
University of British
Columbia, 6224
Agricultural Road,
Vancouver, BC, V6T
1Z1
The contact angle for a super-hydrophobic material has
been estimated by various methods. A simple example is
Wenzel’s model [8] as shown in Equation (2) below.
cos θrough = r cos θsmooth = r
( γ sv − γ sl )
γ lv
(2)
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... TOTAL INTERNAL REFLECTION ... (WHITEHEAD ET AL.)
Fig. 2
Water drop resting on a super-hydrophobic surface.
This is a modified version of Young’s equation, in which the
roughness factor, r, is defined as the ratio of the total area of a
rough surface to the effective surface area of the tips that is in
contact with the water drop. This value of the surface area ratio
is always greater than 1, so the contact angle for a rough surface will always be greater than that of a smooth surface.
In addition to having a myriad of practical applications in
industry, hydrophilic, hydrophobic and super-hydrophobic
materials also occur in some naturally-adapted forms. Perhaps
the best known example is the leaf of the lotus plant, a type of
water lily that is native to Asia. Scanning electron micrograph
images have shown that surface of the lotus leaf has microscopically small bumps and tiny hair-like structures. Together
with the naturally hydrophobic properties of the waxy leaf
material, these nano-scale surface features give rise to a superhydrophobic surface with a contact angle of greater than
150o [9].
It is thought that this surface evolved as a self-cleaning mechanism. The water drop actually makes very little contact with
the highly convoluted surface, which means that raindrops
roll down the leaf with very little friction. Along the way, the
raindrop collects dirt and bacteria, thus cleaning the leaf. This
explains how the lotus’ leaves remain extremely clean,
even though the water tends to be very dirty in their natural
pond habitat. The existence of this natural phenomenon has
fascinated scientists since it was first understood in 1975 [9,10]
and it initiated an important branch of nanotechnology
research [11-13].
THE STRUCTURE OF AN ARBUTUS LEAF
We have recently observed that the leaf of the arbutus tree
exhibits a similar super-hydrophobic property. The arbutus
tree, a photograph of which appears in Figure 3, is a broadleaf
evergreen tree with unusually smooth, orange bark and red
berries. It grows in a very limited area in North America, in
small comparatively dryer pockets near the sea, between southern British Columbia and the northern California.
8 C PHYSICS
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Fig. 3
An arbutus tree, native to southern coastal British Columbia.
Interestingly, in the case of the arbutus leaf, it is only the underside of the leaf that exhibits the super-hydrophobic property.
One might wonder what the evolutionary advantage of such an
arrangement may have been. Since the stomata (the gas transport pores in the leaf) are on the underside, perhaps there may
have been an advantage in keeping them free of a water film in
order to maintain air flow. Given the relatively pristine environment in which the tree grows, maintaining a clean top surface may not have been problematic, and the small benefit of a
hydrophobic leaf top surface may have been outweighed by the
metabolic cost of such a coating and/or a resultant reduction in
light transmission – a problem that would be more significant
in a northern climate.
At any rate, we have examined the surface structure and have
confirmed that it has hair-like features with a diameter of about
100 nm and spacing of about 1000 nm as shown in the scanning electron micrograph in Figure 4.
We cannot accurately determine the roughness factor, r, from
such an image. However, it appears to lie approximately in the
range from 3 to 5. If the materials from which the hairs form
have a mildly hydrophobic contact angle of about 100o, then
the application of Wenzel’s law would yield a net contact angle
in the range 120o to 150o. We placed a 2 mm diameter water
drop on the surface of the leaf, as shown in Figure 5, and
observed a contact angle of approximately 140o, consistent
with the SEM observations and such considerations.
The existence of this super-hydrophobic property on the arbutus tree is not in itself scientifically noteworthy (although as
mentioned above it is interesting that it is restricted to the leaf
underside). Rather, it is the combination of this natural super-
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... TOTAL INTERNAL REFLECTION ... (WHITEHEAD ET AL.)AA
all angles of incidence greater than the critical angle, the light
will be completely reflected by means of TIR. As an example,
the critical angle for a water/air interface where ni = 1.334 and
nt = 1.000 is 48.8o.
When TIR is occurring, there is no net transfer of electromagnetic energy across the interface, but the complete solution of
the Maxwell equations shows that a small amount of the electromagnetic field energy actually penetrates a small distance
into the second material. This phenomenon, referred to as an
evanescent wave, corresponds to a propagation of energy along
the interface with an intensity that decreases exponentially as a
function of depth into the second material. The mean penetration depth is usually less than a half wavelength, which for visible light is about 250 nm. This concept is depicted schematically in Figure 6.
Fig. 4
Scanning electron micrograph of the underside of an
arbutus leaf.
hydrophobicity with another well-known, but unrelated, phenomenon in physics, total internal reflection, which we present
here as an interesting demonstration of physics in nature.
TOTAL INTERNAL REFLECTION AT A SUPERHYDROPHOBIC INTERFACE
Total internal reflection (TIR) is an optical phenomenon that
can occur when a light ray traveling in a transparent material
with index of refraction ni encounters an interface with a material having a lower index of refraction, nt. The occurrence of
TIR depends on the angle of incidence and the ratio of the
refractive index values of the two materials. This ratio determines a critical angle, θc, for the interface, as shown in
Equation (3):
⎛n ⎞
θc = sin−1 ⎜ t ⎟
⎝ ni ⎠
(3)
By convention, angles of incidence are measured from a reference direction perpendicular to the surface in question. If this
value is less than the critical value, the light will partially
reflect and partially transmit into the second material, but for
Fig. 6
Total internal reflection occurring at an interface.
It is also well known that TIR can be prevented, or “frustrated”,
by absorbing the energy in the evanescent wave, which can be
done by moving an absorptive or optically dense material into
the region near the interface that is occupied by the evanescent
wave. For practical purposes, this means that as long as the
second lower index material extends a distance equivalent to
several penetration depths of the evanescent wave, TIR will
efficiently occur. Interestingly, because of the small thickness
of the evanescent wave, this means the required thickness is
about 1 or 2 μm.
TIR has been well-studied and is useful in a number of important applications, perhaps the most notable being the propagation of electromagnetic waves in fibre optic communication
systems. Moreover, although it is rare, the phenomenon of TIR
can occasionally be viewed in nature, for example in a
mirage [14], and recently we have observed that a waterimmersed arbutus leaf provides another such natural occurrence.
Fig. 5
A water drop on an arbutus leaf exhibits a contact angle
of 140o.
Considering again the micrograph image in Figure 4, it appears
that at least 90% of the volume in the structured surface region
is comprised of air, and that therefore the effective refractive
index of this region should be close to 1.0, perhaps approximately 1.05. This region is several micrometers thick and
therefore ought to be sufficient to cause total internal reflection
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Page 10
when immersed in water, given that this index value is much
less than the value of 1.334 for that liquid. Furthermore, the
super-hydrophobic nature of the surface should ensure that a
low index value is maintained in the presence of water, as it
would be energetically unfavourable for water to fill the nanoscale voids.
Such expectations are indeed realized when the leaf is viewed
underwater, as shown in Figure 7. For small angles of incidence, the leaf looks like a leaf; for large angles of incidence
the leaf looks like a piece of silver; and at approximately the
anticipated critical angle, the angular variations within the leaf
cause a mixed appearance.
QUANTIFYING THE REFLECTION CHARACTERISTICS
In order to establish that the observed reflectance is caused by
TIR, we have measured it by comparing the surface luminance
to that of a specular metallic surface of known reflectance Rs
(aluminized polyester film, Rs . 85%). The leaf was immersed
in water in a transparent tank within a diffusely reflective 1 m
diameter integrating sphere illuminated uniformly by a 50 W
3000 K quartz-halogen incandescent lamp powered by a regulated DC supply. Front surface reflection from the tank was
minimized by carefully aiming the reflected view from that
surface toward a small black patch. We used a photometric
luminance meter to measure the luminance of an 8 mm circular region on the leaf and that of the immediately adjacent coplanar specular reference surface, over a 60o angular range
spanning the anticipated critical angle, which for an interface
between pure water and a mixture of 10% polymer (with index
about 1.5) and 90% air (with index of 1.0) would be about 52o.
Figure 8 shows that when the leaf is immersed in water, as
compared to when it is immersed in air, the reflectance does
rapidly increase to a high value that is close to 100% as the
viewing angle moves through the region near the anticipated
critical angle.
Fig. 7
Photograph of TIR occurring on the underside of an
arbutus leaf.
While the reflection shown in Figure 7 is remarkably longlived under ordinary conditions, we were able to show that it
could be easily destroyed in two ways, both of which remove
the air. The first way was to add detergent to the water, lowering the surface tension of the air-water interface. In this case,
the observed TIR appearance vanished within seconds. The
second way was to submerge the leaf in de-aired water, (prepared by vigorously boiling the water and then cooling it in a
sealed container). In this case, the leaf at first appears highly
reflective as in Figure 7, but over a few minutes the TIR
appearance fades away, presumably as the air dissolves into the
water.
It should also be noted that super-hydrophobic leaves are not
the only immersed super-hydrophobic surfaces capable of
appearing highly reflective. We have observed that a commercially available spray-on super-hydrophobic coating [15] has a
similar effect. And considering again naturally occurring systems, there have been anecdotal reports of the “silvery” appearance of the plastrons of certain insects underwater [16,17], an
effect that is presumably caused by a similar phenomenon. At
any rate, the comparatively flat undersurface of the arbutus leaf
has provided an opportunity whereby this naturally-observed
effect can be measured in order to establish that TIR is indeed
taking place.
10 C PHYSICS
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Fig. 8
Reflectance of immersed leaf as a function of viewing angle.
It is interesting to consider how the reflectance measurements
carried out in air relate to those done in water. In both cases,
we believe the reflective surface of the leaf is in contact with
the super-hydrophobic layer, which is mainly air, and this leaf
reflectance, which we can label Rla should therefore be the
same. The difference caused by measuring under water is simply the addition of one optical interface – that between the
water and the super-hydrophobic layer, whose reflectance can
be labeled Raw. When two reflective surfaces are adjacent to
one another, and incoherent light is employed, the combined
reflectance R is easily determined by calculating the rapidly
converging sum of the infinite series of inter-reflections. It is
thus straightforward to show that these reflectance values are
related as shown in Equation (3):
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... TOTAL INTERNAL REFLECTION ... (WHITEHEAD ET AL.)AA
R = Raw +
Rla (1 − Raw )2
1 − Rla Raw
(3)
By inverting this relation we obtained the values of Raw that
would be required to yield the observed values of R and Rla of
Figure 8. These measurement-derived Raw values are plotted in
Figure 9.
We can now consider whether these values for Raw are those
that would be expected for such an interface. To check this, we
calculated the anticipated reflectance for non-polarized incoherent light using the Fresnel equations as shown in
Equation 4:
R=
1 ⎛ sin2 (θt − θi ) tan2 (θt − θi ) ⎞
+
⎜
⎟
2 ⎝ sin2 (θt + θi ) tan2 (θt + θi ) ⎠
(4)
where θt is determined from Snell’s law, θt = sin-1 ((ni/nt)
sin(θi )), and θi and θt are, respectively, the incident and transmitted angle. For ni we used the known value for the refractive
index of water, 1.334, and for nt we used an estimated value of
1.05 for the effective refractive index of the super-hydrophobic
fibre/air layer. To take into account the slightly non-planar
nature of the leaf surface we convoluted the result with a
Gaussian angular distribution, finding that adjusting the standard deviation to a reasonable value of 8o gave the best fit.
(This value was confirmed to be reasonable by directing a laser
beam, with an angle of incidence greater than θc, at the surface
of the leaf and observing the angular spread of the reflected
light.) As shown in Figure 9, these calculated values agree reasonably well with those derived from the measurements in
Figure 8.
These observations leave little doubt that the observed
reflectance is indeed the result of total internal reflection at the
boundary between the water and the air-filled super-hydrophobic layer.
DISCUSSION
The measurement of total internal reflection on the surface of
an arbutus leaf has enabled a quantitative evaluation of an
effect that has been observed in several other naturally-occurring super-hydrophobic systems. When the super-hydrophobic properties of the lotus leaf first were first understood, a
wide range of biomimetic research ensued, including development of new non-wetting and self-cleaning materials.
Similarly, although the work reported here focuses on a natural
phenomenon and not on any specific application, it has
nonetheless stimulated our interest in possible optical uses of
super-hydrophobic layers. In particular, it is interesting to consider means of controlling the degree of reflection of a superhydrophobic surface. Such controlled reflection could be useful in a number of areas, including optical switches, beam
steering systems and electronic image displays.
CONCLUSION
To the best of our knowledge this paper represents the first
quantitative verification of total internal reflection in underwater air-filled super-hydrophobic nano-structured films, but the
advancement of scientific knowledge is not the primary goal of
this paper. Rather, our view is that arbutus leaves serve as an
interesting natural manifestation of a phenomenon that might
otherwise have only been observed through experimentation in
a research laboratory. Just as a rainbow tells us little new about
refraction, dispersion or diffraction, these arbutus leaf observations have not advanced our understanding of total internal
reflection. However, it is worthwhile (and non-trivial) to
understand a rainbow, and similarly, we hope the work
described here may advance in a small way our appreciation of
nature and the remarkable complexities of evolved nanostructures that employ subtle physical laws and are essential to all
forms of life.
ACKNOWLEDGEMENTS
The authors thank the Natural Sciences and Engineering
Research Council of Canada and 3M Company for their support of this work. The authors are also grateful to Dr. Peter
Hrudey for his contributions to this paper.
Fig. 9
Reflectance of the air-water interface for the immersed leaf.
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REFERENCES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
F. White, Fluid Mechanics, McGraw-Hill, New York, p. 30, 1986.
T. Young, “An essay on the cohesion of fluids”, Philos. Trans. R. Soc., 95, 65-87 (1805).
T. Yasuda, T. Okuno and H. Yasuda, “Contact Angle of Water on Polymer Surfaces,” Langmuir, 10, 2435-2439 (1994).
T. Nishino, M. Meguro, N. Katsuhiko, M. Matsushita, and Y. Ueda, “The lowest surface free energy based on CF3 alignment,”
Langmuir, 15, 4321–4323 (1999).
A. Cassie and S. Baxter, “Wettability of porous surfaces”, Trans. Faraday Soc., 40, 546-551 (1944).
S. Herminghaus, “Roughness-induced non-wetting”, Europhys. Lett., 52, 165–170 (2000).
A. Nakajima, H. Kazuhito, and T. Watanabe, “Recent studies on super-hydrophobic films”, Monatsh. Chem., 132, 31–41 (2001).
R. Wenzel, Ind. Eng. Chem., 28, 988 (1936).
C. Neinhuis and W. Barthlott, “Characterization and distribution of water-repellent, self-cleaning plant surfaces”, Ann. Bot., 79, 667677 (1997).
W. Barthlott and C. Neinhuis, “Purity of the sacred lotus, or escape from contamination in biological surfaces”, Planta, 202, 1-8
(1997).
H. Erbil, A. Demirel, Y. Avci and O. Mert, “Transformation of a simple plastic into a super-hydrophobic surface”, Science, 299, 13771380 (2003).
D. Quere, A. Lafuma and J. Bico, “Slippy and sticky microtextured solids”, Nanotechnology, 14, 1109-1112 (2003).
N. Shirtcliffe, G. McHale, M. Newton, C. Perry and B. Pyatt, “Plastron properties of a super-hydrophobic surface”, Appl. Phys. Lett.,
89, 104106 (2006).
L. Whitehead, M. Mossman, and A. Kotlicki, “Visual applications of total internal reflection in prismatic microstructures”, Physics in
Canada, 57, 329-335 (2001).
HIREC 100™, NTT Advanced Technology Corporation, Shinjuku Mitsui Building 2-1-1, Nishi-shinjuku, Shinjuku-ku, Tokyo 1630431, Japan.
W. Lee, M.K. Jin, W.C. Yoo and J.K. Lee, “Nanostructuring of a polymeric substrate with well-defined nanometer-scale topography
and tailored surface wettability “, Langmuir, 20, 7665-7669 (2004).
X. Gao and L. Jiang, “Water-repellent legs of water striders”, Nature, 432, 36 (2004).
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ARTICLE DE FOND
A PHOTONICS PATH
TO
STRUCTURAL MONITORING
FABIEN RAVET AND XIAOYI BAO
BY
I
n 1920, when Leon Brillouin presented his thesis
“Diffusion de la lumière et des rayons X par un corps
transparent et homogène – Influence de l’agitation
thermique1”, he probably did not suspect that his discovery would still generate passionate interest in the twenty first century [1]. His research led to the conclusion that
density fluctuations in the medium resulted in thermally
generated sound waves. That thermal agitation is capable
of scattering incident lightwave inelastically, i.e. the scattering has shifted frequency2. In 1930, Gross’s experiments [2] showed that the scattered spectra included two
Brillouin components and one unshifted peak (Fig. 1), the
so called Rayleigh scattering. The Brillouin peaks are the
Stokes and the anti-Stokes lines, which are down- and upshifted in frequency, respectively. These frequency shifts
are proportional to the acoustic mode velocity and are
called Brillouin frequency, i.e. the broadening of the peaks
is due to the attenuation of the sound waves. Landau and
Placzek (1934) explained that the central line is due to
non-propagating temperature fluctuations [2,3]. The field
then did not really progress due to the lack of intense
monochromatic sources and sensitive spectrometers. The
advent of the laser (circa 1964) brought new advances to
the topic [4]. With the development of high-resolution
spectrum analysers, accurate measurements of the frequencies, intensities and linewidths of the various lines are
possible giving access to the characterisation of acoustic
and thermodynamic properties of materials e.g. sound
velocity, sound attenuation coefficients, elastic constants,
and isothermal compressibility. These properties are still
studied with the help of Brillouin scattering [5]. The seventies saw the introduction of optical fibres and the first
SUMMARY
Disaster prevention in civil infrastructures
requires the use of techniques that allow
temperature and strain measurements in real
time over lengths of a few meters to tens of
kilometres. The distributed Brillouin sensor
(DBS) technique has the advantage to combine all these characteristics. The sensing
mechanism of the DBS involves the interaction of two counter-propagating lightwaves,
the Stokes and the pump, in an optical fibre.
In this article, we introduce the DBS physics
and illustrate how it can be used in civil and
structural engineering.
observations of spontaneous and stimulated Brillouin scattering in silica waveguides [6,7]. Here the interest was triggered by the impairment caused by the stimulated
Brillouin scattering in transmission links [8]. Since then,
the interest never ceased, as many potential applications of
Brillouin scattering in optical fibres were investigated.
We can mention optical amplifiers [9], fibre lasers [10], narrowband and tuneable filtering [11]. More recently,
researches have shown that the propagation time of pulses
in optical fibres can be controlled thanks to the Brillouin
resonance[12,13]. Among all these applications, we retain
the works of Horiguchi and Culverhouse, both in 1989,
where the authors demonstrated that Brillouin scattering
can be used to measure strain and temperature respectively, initiating a prolific research in fibre optic sensors [14,15].
Fig. 1
Schematic of the observed scattered light intensity.
Frequency and intensity axis are not scaled to reproduce
accurately the peaks heights and frequencies.
STRUCTURAL HEALTH MONITORING
The sensing capabilities of Brillouin scattering are certainly of interest for civil engineering applications where a
new field, known as Structural Health Monitoring (SHM),
is currently developing. According to Bisby [16],
“….structural health monitoring can be defined as a nondestructive in-situ structural evaluation method that uses
any of several types of sensors which are attached to, or
embedded in, a structure. These sensors obtain various
types of data (either continuously or periodically), which
are then collected, analyzed and stored for future analysis
and reference. The data can be used to assess the safety,
integrity, strength, or performance of the structure, and to
identify damage at its onset.” Various factors have driven
the emergence of SHM. First, public infrastructures of
industrialised countries are subjected to a strong “pres-
Fabien Ravet*
and Xiaoyi Bao
([email protected]),
Canada Research
Chair in Fibre Optics
and Photonics,
Physics Department,
University of Ottawa,
150 Louis Pasteur,
Ottawa, ON, K1N
6N5
* current address:
Omnisens SA, 3 Riond
Bosson, CH-1110
Morges, Switzerland,
1. The thesis can be translated as “Light and x-rays scattering by a
transparent homogeneous body – Effect of thermal agitation”. The
work was published as an article in 1922 (Brillouin 1922).
2. The same effect was studied independently by Mandelstham and published in 1926 (Schroeder 1977).
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... STRUCTURAL MONITORING (RAVET AND BAO)
sure” on ‘safety’. Civil structures are overused, leading to
accelerated ageing. Moreover, the infrastructures are often old
not to say obsolete e.g. 40% of the bridges in Canada are 50
years old [16]. In many cases, replacement is not immediately
possible due to a lack of public funding. Instead, strengthening and rehabilitation are considered as an option that would
increase the lifetime of the current infrastructure. Determining
the lifetime of the structure is then critical, which is only possible if an inspection strategy is in place. SHM can then be
implemented to identify early signs of potential problems,
allowing for prevention of disasters and repair of the damage.
Second, SHM is also a tool to improve the construction
processes for new building materials and structures. These
innovative structures response to stress can be studied thanks to
a systematic layout of sensors and to the monitoring of their
outputs. One of the most spectacular and recent example is
certainly the Confederation Bridge (Fig. 2).
Fig. 2
Confederation bridge: an example of structure combining
innovative design and SHM techniques.
FIBRE OPTIC SENSORS
Among the various sensing technologies that are considered for
SHM, fibre optic sensors (FOS) are the most promising candidates [17-20]. Their advantages are inherent to the optical fibre
properties. Being made of silica, the sensing medium is made
of dielectric materials, which are immune to electromagnetic
interferences. The sensors can be installed in remote locations
as the fibre is a low loss transmission medium. Fibre optic sensors are small, light and non-corrosive, implying that they can
be embedded without impacting significantly the structure
design. Finally, optical fibre technology is now a field mature
enough so that the sensors can be laid on any structure shape
and size i.e. a broad variety of optical components allows the
multiplexing and the cascading of sensors. In addition, that
capability is enhanced by the sensor type. In fact, FOS can be
divided into two categories: point and distributed sensors. For
point sensor, the sensing length (or gauge length) varies from
centimetres to tens of meters. The sensing part is connected to
the light source and the detection system by an optical fibre
communication cable. In this category we find fibre Bragg
gratings (FBG) and Fabry-Perot (FP) sensors. Long gauge
(LG) sensors, which are based on a Michelson interferometer
design, measure average strain over the gauge length, which
can be as large as 200 m. In the case of distributed FOS, the
fibre itself is the sensing medium, at any location, and the
gauge length can be as small as tenths of metres over distances
as long as tens of kilometres.
The monitoring techniques must be able to detect faults and
assess the severity of the damage of whole structures such as
pipelines, bridges, dams or river levees. Ideally, the sensors
must perform distributed temperature or/and strain measurements over a few meters to tens of kilometres in real time.
Those requirements can easily be met by the use of distributed
sensors.
DISTRIBUTED SENSORS
Three physical effects are identified as mechanisms for distributed sensing: Rayleigh, Raman and Brillouin scattering. The
simplest distributed sensor is based on Rayleigh scattering and
is widely used in optical communications to qualify optical
links [21]. It is known as the optical time domain reflectometer
(OTDR). As the Rayleigh peak temperature dependence in
normal fibres is weak, its implementation as a sensor requires
the development of non-standard fibres3. These fibres have a
liquid core [22], or, special core dopants that makes the
Rayleigh peak more sensitive to temperature changes [23].
Special cables can also be used that convert the physical quantity (temperature, strain, pressure) variation into excess loss[24].
Raman scattering is another effect that can be exploited to
measure temperature over 10 kilometres to the maximum [25].
Here, the sensing function is achieved by computing the ratio
of the measured Stokes to anti-Stokes intensities, as it is an
exponential function of temperature. At last but not least is the
Brillouin sensor technique, which is capable of measuring both
temperature [14] and strain [15] up to 50 km kilometres without
signal regeneration [26]. In the Brillouin sensor, the sensing
mechanism takes advantage of the linear relationship between
the Brillouin frequency and temperature/tensile strain variations (Fig. 3). The Brillouin sensor has clearly an advantage
over the other technologies as it can perform temperature and
Fig. 3
The Brillouin frequency is proportional to temperature and
strain.
3. The adjective “standard” used in the present article refers to optical fibres that are used in optical communications and whose nominal characteristics are determined by standardization bodies such as the International Telecommunication Union or the International Electrotechnical Committee.
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... STRUCTURAL MONITORING (RAVET ET BAO)AA
strain measurement. Brillouin sensor classification can be
refined further by considering the configuration of the sensor.
Two layouts can be distinguished which are Brillouin backscattering and stimulated Brillouin scattering configurations. We
will focus our attention on the stimulated Brillouin scattering
configuration.
STIMULATED BRILLOUIN SCATTERING
CONFIGURATION
In the stimulated Brillouin scattering configuration, two lightwaves, the pump and the probe signals, are launched into the
fibre in a counter-propagating configuration. The simultaneous
presence of the Stokes and the pump waves generate a beat signal that reinforces the acoustic wave in the fibre when the
beams frequency difference is equal to the Brillouin frequency.
The coupling mechanism between the two lightwaves is electrostriction, which is the ability of a centro-symmetric material
to change density when an electric field is applied. The scattering of the pump is then enhanced, leading to its depletion
and the input probe beam is amplified. The probe is also called
Stokes as it corresponds to the frequency downshifted peak.
The Brillouin spectrum can be recorded by tuning the frequency difference between pump and Stokes waves. In our sensing
configuration, distributed information is obtained by pulsing
one of the two light sources, the sensor is called Brillouin optical time domain analyser (BOTDA) [27]. The pulsewidth determines the spatial resolution of the sensor and then its gauge
length. The signal detection is performed at the fibre end in
which the modulated lightwave is launched. The sensor configuration used at the university of Ottawa is based on the
Brillouin loss type BOTDA [27-29] and is presented in Fig. 4. In
that configuration, the Stokes wave is pulsed and the sensor
records the pump output intensity variation. The pump is then
attenuated at the profit of the Stokes signal.
smallest detectable event size, the frequency resolution, which
is the smallest Brillouin frequency shift that can be measured,
and the measurement range, which is the longest length over
which the sensor can make an accurate data acquisition.
EXAMPLES OF APPLICATIONS
The first pipe case studied was the monitoring of a distribution
pipe subjected to extreme load conditions [30,31]. In that experiment a vertical load was applied to the structure. Buckling
occurred at the current loading level because the inner wall was
locally thinned to create a
weakness that would act as a
failure trigger (Fig. 5). The
buckling formation could be
anticipated by watching for
multiple strain components
over the pulse length, especially at the tension site. Those
components lead generally to
multiple peak Brillouin spectra
Fig. 5 Buckled pipe with
at the buckling location
sensing fibres (brow
(Fig. 6).
strips).
PERFORMANCE PARAMETERS
Various parameters need to be considered when comparing the
Brillouin sensor systems. First, one has to keep in mind that
the sensor must be implemented on the field. It must then be
simple to install and complete the sensing operation as quickly
as possible. Second, some of the sensor performances are critical. Those are the spatial resolution, which indicates the
Fig. 4
Experimental set-up of the distributed Brillouin sensor.
Fig. 6
Brillouin spectrum measured at buckling location.
We conducted another monitoring experiment on a concrete
column strengthened with fibre reinforced polymer sheets [3234]. The column was subjected to an axial load while successively bended back- and forward with increasing loads, simulating seismic induced stress conditions. For a concrete/FRP
(fibre reinforced polymer) column, the structure is non uniform
and inhomogeneous by construction. Even a light stress would
induce quite a large Brillouin spectrum distortion. The spectra
would appear asymmetric and broadened. We developed an
approach based on the spectrum shape analysis to analyse the
structure behaviour [33]. We see that our sensor system is not
only capable of measuring deformation of the structure as illustrated in Fig. 7. It also gives enough information so that engineers can correlate the readings with the applied stresses and
deduce the possible de-bonding of the FRP and concrete as
well as the crack conditions (Fig. 8).
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... STRUCTURAL MONITORING (RAVET AND BAO)
Fig. 7
Axial profile of peak strain for (a) left face and (b) right faces
under respectively a left and right horizontal loads. Open
symbol curves correspond to a lateral displacement of 8% of
the column height and full symbols are associated with a
deviation of 4%.
CONCLUSIONS
Following two recent bridge fallings: 1) On September 30,
2006, part of an overpass (65 foot section of a three-lane overpass collapsed in Laval, a suburb of Montreal, on Concorde
boulevard running over Autoroute 19. The collapse crushed
two vehicles under it, killing five people and seriously injuring
six others who went over the edge while travelling on the overpass. The bridge was inspected in 2005 without major problem.
2) A major highway bridge in Minneapolis buckled during rush
hour on Wednesday night (August 1, 2007), forcing dozens of
cars to plummet into the Mississippi River. The Minnesota
governor said a 2006 inspection of the bridge found no immediate structural problems. Both events show the importance of
improving the state of the practice for bridge management via
an accurate assessment of bridge condition and performance.
This can only be achieved by better understanding the bridge
condition through developing advanced health monitoring
tools comprising both remote and onsite evaluation and distributed Brillouin sensor is one of the most promising tools to
serve the need of the structural health monitoring for bridge
and other large civil structures. Finally we need to relate health
monitoring findings to structural condition.
Fig. 8
Post-mortem analysis of the column: concrete at the bottom part
has been crushed; once FRP is
removed, concrete dust flown on
the column support.
The purpose of the structural health monitoring is
to protect and prolong
the useful life of structures, and to identify
problems & trigger follow-up action (Condition
survey, evaluation, etc),
as well as to gather
enough information to
estimate bridge rehabilitation and maintenance
needs.
This requires
engineers and scientists
from different fields
work together to ensure
an acceptable standard
for structures in terms of
public safety, comfort
and convenience.
Distributed
Brillouin
sensors, whose operation
principles were described
in this article, are one of the most promising diagnostic tools
that could help improve the structural health monitoring
process. Their insensitivity to the harsh environmental conditions, along with the low investment costs required for their
integration into the new or existing infrastructures, makes them
an ideal candidate for structural health monitoring applications
ACKNOWLEDGEMENT
The authors want to acknowledge the financial support of
Natural Science and Engineering Research Council Canada,
Intelligent Sensing for Innovative Structures Canada, whose
funding was appreciated very much.
REFERENCES
1.
2.
3.
4.
5.
6.
7.
8.
Brillouin, L., “Diffusion de la lumière et des rayons X par un corps transparent homogène”, Annales de Physique, 17: 88-122 (1922).
Schroeder, J., “Light scattering of glass”, Treatise on material science and technology, Volume 12. Glass I: interaction with electromagnetic radiation, Academic Press: 157-222 (1977).
Landau, L., and, Lifchitz, E., Electrodynamique des milieux continus, Editions Mir, Moscou (1969).
Chiao, R.Y., Townes, C.H., and Stoicheff, B.P., “Stimulated Brillouin Scattering and Coherent Generation of Intense Hypersonic
Waves”, Physical Review Letters 12: 592-595 (1964).
Levelut, C., Le Parc, R., and Pelous, J., “Dynamic sound attenuation at hypersonic frequencies in silica glass”, Physical Review B, 73:
052202 (2006).
Ippen, E.P., and Stolen, R.H., “Stimulated Brillouin scattering in optical fibers”, Applied Physics Letters 21: 539-541 (1972).
Rich, T.C., and, Pinnow, D.A., “Evaluation of fiber optical waveguides using Brillouin spectroscopy”, Applied Physics Letters 13: 264266 (1974).
Smith, R.G., “Optical power handling capacity of low loss optical fibers as determined by stimulated Raman and Brillouin scattering”,
Applied Optics, 11: 2489-2494 (1972).
16 C PHYSICS
IN
3/11/2008
12:04 PM
Page 17
... STRUCTURAL MONITORING (RAVET ET BAO)AA
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
Olsson, N.A. and van der Ziel, J.P., “Cancellation of fiber loss by semiconductor laser pumped Brillouin amplification at 1.5 ?m”,
Applied Physics Letters, 48: 1329-1330 (1986).
Bayvel, P., Giles, I.P., and Radmore, P.M., “Transients and steady-state characteristics of a Brillouin amplifier based on an all-fibre
single-mode ring resonator”, Optical and Quantum Electronics, 21: S113-S128 (1989).
Tkach, R.W., Chraplyvy, A.R., and Derosier, R.M., “Performance of a WDM network based on stimulated Brillouin scattering”, IEEE
Photonics Technology Letters, 21: S105-S112 (1989).
Okawachi, Y., Bigelow, M.S., Sharping, J.E., Zhu, Z., Schweinberg, A., Gauthier, D.J., Boyd, R.W., and, Gaeta, A.L., “Tunable alloptical delays via Brillouin Slow Light in an Optical Fiber”, Physical Review Letters, 94: 153902 (2005).
Song K.-Y., González-Herráez, M., and Thévenaz, L., “Observation of pulse delaying and advancement in optical fibers using stimulated Brillouin scattering”, Optics Express, 13: 82-88 (2005).
Horiguchi, T., Kurashima, T. and Tateda, M., “Tensile strain of Brillouin frequency shift in silica optical fibers”, IEEE Photonics
Technology Letters, 1: 107-108 (1989).
Culverhouse, D., Frahi, F., Pannell, C.N., and, Jackson, D.A, “Potential of stimulated Brillouin scattering as sensing mechanism for
distributed temperature sensor”, Electronics Letters, 25: 913-915 (1989).
Bisby, L.A., ISIS educational module 5: an Introduction to structural health monitoring, ISIS Canada (2004).
Kersey, A.D., “A review of recent developments in fiber optic sensor technology”, Optical Fiber Technology, 2: 291-317 (1996).
Tennyson, R.C., Coroy, T., Duck, G., Manuelpillai, G., Mulhivill, P., Cooper, D.J.F., Smith, P.W.E., Mufti, A.A., and, Jalali, J.J., “Fibre
optic sensors in civil engineering structures”, Canadian Journal of Civil Engineering, 27: 880-889 (2000).
Culshaw, B., “Optical fiber sensor technologies: opportunities and-perhaps-pitfalls”, Journal of Lightwave Technology, 22: 39-50
(2004).
Thévenaz, L., “Review and progress in distributed fiber sensing”, 18th International Conference on Optical Fibre Sensors OFS 2007,
Cancun (Mexico), October 23-27, 2006, Technical Digest of the Optical Society of America, Paper ThC6 (2006).
Hartog, A.H., and Gold, M.P., “On the theory of backscattering in single-mode optical fibers”, Journal of Lightwave Technology, 2:
76-84 (1984).
Hartog, A.H., “A distributed temperature sensor based on a liquid-core optical fibre”, Journal of Lightwave Technology, 1, 498 (1983).
Farries, M.C., Fermann, M.E., Laming, R.I., Poole, S.B. and Payne, D.N., “Distributed temperature sensor using Nd3+ doped fiber”,
Electronics Letters, 22: 418-419 (1986).
Maclean, A., Moran, C., Johnstone, W., Culshaw, B., Marsh, D., and Parker, P., “Detection of hydrocarbon fuel spills using a distributed fibre optic sensor”, Sensors&Actuators: A. Physical, 109: 60-67 (2003).
Dakin, J.P., Pratt, D.J., Bibby, G.W., and Ross, J.N., “Distributed optical Raman temperature sensor using a semiconductor light source
and detector”, Electronics Letters, 21: 569-570 (1985).
Bao, X., Dhliwayo, J., Heron, N., Webb, D.J., and Jackson, D.A. “Experimental and theoretical studies on a distributed temperature
sensor based on Brillouin scattering”, Journal of Lightwave Technology, 13: 1340-1348 (1995).
Horiguchi, T., and Tateda, M.Y., “BOTDA-nondestructive measurement of single-mode optical fibers attenuation characteristics using
Brillouin interaction: theory”, Journal of Lightwave Technology, 7: 1170-1176 (1989).
Bao, X., Webb, D.J., and Jackson, D.A., “32-km distributed temperature sensor based on Brillouin loss in an optical fiber”, Optics
Letters, 18: 1561-163 (1993).
Bao, X., Webb, D.J, and Jackson, D.A., “ombined distributed temperature and strain sensor based on Brillouin loss in an optical fiber”,
Optics Letters, 19: 141-143 (1994).
Ravet, F., Zou, L., Bao, X., Chen, L., Huang, R.F., and Khoo, H.A., “Pipeline buckling detection by the distributed Brillouin sensor”,
Sensing Issues in Civil Structural Health Monitoring, Farhad Ansari Editor, Springer Verlag: 515-523 (2005).
Ravet, F., Zou, L., Bao, X., Chen, L., Huang, R.F., and Khoo, H.A., “Detection of buckling in steel pipeline and beam by the distributed Brillouin sensor”, Optical Fiber Technology, 12: 305-311 (2006).
Ozbakkaloglu, T. and Saatcioglu, M., “Seismic performance of square high-strength concrete columns in FRP stay-in-Place formwork”, Journal of Structural Engineering, 133: 44-56 (2007).
Ravet, F., Bao, X., Ozbakaloglu, T., and Saatcioglu, M., “Signature of structure failure using asymmetric and broadening factors of
Brillouin Spectrum”, IEEE Photonics Technology Letters, 18: 394-396 (2006).
Ravet, F., Zou, L., Bao, X., Ozbakkaloglu, T., Saatcioglu, M., and Zhou, J., “Distributed Brillouin sensor for structural health monitoring”, Canadian Journal of Civil Engineering, 34: 291-297 (2007).
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18 C PHYSICS
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ARTICLE DE FOND
GIANT MAGNETORESISTANCE AND
MAGNETIC RECORDING INDUSTRY
BY
ITS IMPACT ON THE
MARK JOHNSON
t the beginning of the new millennium, in 2000,
the Nobel prize committee acknowledged seminal work that led to the unprecedented success
of the semiconductor industry. The development of the microchip began with the invention of the
integrated circuit (IC), generally credited to Jack Kilby [1]
and Robert Noyce (1927-1990) [2]. Half of the 2000 Nobel
Prize for Physics was given to Jack Kilby.
A
IC, which uses lithographic processing to manufacture a
large number of logic or storage devices and link them
together with conducting passageways. The latter is the
complementary metal oxide semiconductor field effect
transistor (CMOS FET), a remarkably efficient and scalable switch [8]. The silicon success story is based on continuing incremental improvements of this architecture and
device.
Dr. Noyce and Gordon Moore founded Intel Corporation
in 1968, and Dr. Moore’s prediction that the density of
transistors fabricated on chips would double approximately every year (later modified to two years) became known
as “Moore’s Law” [3]. The logarithmic increase in the
number of transistors per chip has become a hallmark of
modern semiconductor technology. In Fig. 1, the number
of transistors on Intel Processor chips is plotted as a function of time [4]. The number has doubled about twenty
times in 36 years, slightly faster than the predicted rate of
once every two years.
By contrast, the magnetic recording industry has gone
through changes of both architecture and archetype
device. The basic idea of magnetic recording may have
begun in 1888 with Oberlin Smith, who published an idea
for a machine that used a string coated with iron filings
and an electromagnet to record sound [9]. Digital magnetic recording was born in 1956 when IBM introduced the
RAMAC hard disk drive system. It used fifty disks, each
with a two foot diameter, to provide 5 MB of storage. In
early systems, the sensing device for reading bits (the read
head) was an inductive coil of wire. Fringe magnetic field
from the bits recorded in magnetic media extend to the
vicinity of the read head. As bits in a track pass under the
reader, changes of the fringe field generate a small voltage
Although it’s received less attention, the magnetic recording industry has shown equally remarkable achievements.
The open circles in Fig. 1 represent the areal density of
binary data stored in magnetic media as a function of
time [5]. From 1956, areal density has doubled about 26.5
times in 51 years, giving a doubling rate that’s very close
to Moore’s Law. This year, the Nobel committee acknowledged important work in magnetic recording technology
by giving the 2007 Nobel Prize for Physics to Peter
Grunberg and Albert Fert. The spin valve [6], utilizing
Giant Magnetoresistance [7], was the sensing element
used in magnetic hard disk read heads from 1999 to 2005.
Mark Johnson
<mark.b.johnson
@nrl.navy.mil >,
Naval Research
Laboratory,
Washington D.C.
20375
MAGNETIC RECORDING TECHNOLOGY
Semiconductor technology has thrived on a single architecture and a single archetype device. The former is the
SUMMARY
In celebrating the contributions of this year’s
Nobel physics laureates, the broader
achievements of magnetic recording industry are described. Comparisons are made
with semiconductor information processing
technology. The interplay between technology and economic forces that drives future
developments is also discussed.
Fig. 1
Technology trends for the magnetic recording and semiconductor information processing industries. Open
squares (right axis): number of transistors on a chip for
Intel processors [4]. Open circles (left axis): areal density of bits recorded in magnetic hard disk drive media [5].
Lines are guides to the eye. Blue line: inductive read
head. Red line: magnetoresistive read head. Gray highlight represents the time period when GMR read heads
were the dominant sensor in commercial use.
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GIANT MAGNETORESISTANCE ... (JOHNSON)
in the coil. Inductive readers, eventually using thin film wires,
were used for forty years, but the approach was not scalable. As
the areal density increased, the bit size, the fringe magnetic
flux, and the voltage induced in the sensor all decreased.
to dominate the market within a year. Research focused on fabricating sensors with multilayer sandwich stacks, in which
added layers were used to give the intrinsic magnetization an
optimal orientation in the absence of magnetic field.
A true paradigm shift for reading was the development of the
magnetoresistive sensor. The resistance of a ferromagnetic (F )
metal depends on the orientation of its magnetization, a property known as magnteoresistance (MR). For a wire composed
of a transition metal ferromagnet, such as Ni, Fe, Co and their
alloys, the MR can be measured with a sensing current applied
along the wire axis. The resistance differs when the magnetization orientation is parallel with the wire axis compared with
perpendicular, a property called anisotropic magnetoresistance
(AMR). A thin film sensor using AMR can be made using a
geometry such as that shown in Fig. 2(a) [10]. Leads 1 and 2 are
used to measure the resistance of ferromagnetic flim F . This
structure is suspended above the magnetic media. As a track of
bits passes underneath, the fringe magnetic field of each bit
alters the magnetization orientation of F. The modulated resistance R(t) can be detected and correlated with the information
encoded in the bits.
Excitement about the new MR architecture was peaking in the
mid 1980s, and the stage was set for the development of the
giant magnetoresistance (GMR) spin valve. The sensitivity of
AMR sensors was limited by the AMR ratio (resistance change
relative to resistance, ΔR/R), an intrinsic material property with
a value no more than ΔR/R . 3.0% in NiFe or NiCo films. As
described in the next section, Grunberg fabricated a sandwich
structure with two F films separated by a nonmagnetic (N)
layer [6], later called a spin valve [12], and measured
MR = 1.5%. Within a few years, spin valves with MR values of
6 to 10% were common [13,14]. IBM introduced the first spin
valve read head in 1997. Spin valve sensors dominated the
market by the middle of 1999, and remained dominant until the
introduction of tunnel magnetoresistance (TMR) sensors in
2005. During the commercial lifetime of GMR sensors (gray
highlight above the trace in Fig. 1), the areal density increased
by nearly a factor of ten.
Seminal work on magnetoresistive sensing was done at Ampex
Corp. in the 1970s [11]. IBM developed the technology and
made the first commercial product in 1991. This new architecture was so successful that read heads with AMR sensors came
PHYSICS OF SPIN DEPENDENT TRANSPORT
The field of spin dependent transport in the solid state has
developed from several key experiments and theoretical
insights. More than seventy years ago, Mott [15] asserted that a
charge current in a ferromagnetic metal was spin polarized.
Experimental studies began with the demonstration of spin
dependent tunneling (SDT), about forty years ago, by Tedrow
and Meservey [16]. They fabricated planar F/I/S tunnel junctions, where S was superconducting aluminum, F was a transition metal ferromagnet, and I was an aluminum oxide tunel
barrier. Tunnel conductance spectroscopy was used to demonstrate that the current tunneling into the quasiparticle states of
the aluminum was spin polarized. These experiments gave the
first empirical estimate of the fractional polarization, P, of currents in F, P ~ 40%.
Julliere [17] next demonstrated tunnel magnetoresistance
(TMR), at the same time inventing a structure that has now
become the dominant MR device for all applications. For his
Ph. D. thesis, he made a tunneling structure in which he substituted a second F film for the aluminum electrode, F1/I/F2,
thereby inventing the magnetic tunnel junction (MTJ). He
measured a TMR of roughly 10% at cryogenic temperature. Of
greater importance, he demonstrated that the MR of a sandwich
stack containing two F films depended on the relative magneP and M2.
P
tization orientations M1
Fig. 2
(a) Sketch of magnetoresistive sensor for anisotropic magnetoresistive read head [10]. (b) Sketch of GMR sensor used as
read head [25]. Small arrows represent magnetic fringe field
from bits recorded in magnetic media.
20 C PHYSICS
IN
Following this early SDT work, the common opinion was that
any spin polarized current that crossed a F/N interface (where
N is a nonmagnetic metal) would decay inside N on a length
scale of a few angstroms, that of Ruderman - Kittel - Kasaya Yosida (RKKY) interactions. Had this been true, the spin valve
would never have worked. Aronov took the contrary view and
predicted that a current crossing an F/N interface would be spin
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GIANT MAGNETORESISTANCE ... (JOHNSON)AA
polarized for a distance of an electron mean free path or
longer [18]. At about the same time, Silsbee [19], predicted that
such a current would remain spin polarized for a long distance
in N, and that it would generate a nonequilibrium population of
spin polarized electrons (a spin accumulation) having a spatial
distribution identically the same as the spin diffusion length δs
that characterized transmission electron spin resonance
(TESR). He further predicted a converse effect: the presence of
spin accumulation in N would generate an electric voltage at a
separate N/F2 interface, with a magnitude dependent on the relP and M2
P
These
ative orientations of the magnetizations M1
predictions were confirmed by the “Spin Injection” experiment
which used a lateral spin valve, a F1/N/F2 structure in which
the two F films were coplanar [20]. This experiment demonstrated that spin polarized conduction electrons could propagate in N for long distances, and it was the first to demonstrate
a resistance modulation ΔR in a F1/N/F2 structure that changed
P and M2
P changed from parallel to antiparallel.
when M1
Grunberg then followed with a famous set of experiments. The
coupling of the magnetic properties of ferromagnetic and/or
antiferromagnetic films had been studied since the 1950s [21].
There was a renewal of interest in the 1980s [22,23], and
Grunberg led a series of experiments to demonstrate magnetic
coupling of two F films, separated by a N spacer layer [24]. In a
key experiment [6], a Fe / Cr / Fe trilayer sandwich was epitaxially grown, with thicknesses dFe = 12nm and dCr = 1nm.
P and M2
P were antiKerr measurements confirmed that M1
ferromagnetically coupled, having antiparallel orientation in
zero applied field. The MR was measured to be larger than the
AMR of the Fe layers. The beauty of the structure was that it
was readily compatible with existing MR sensor technology
[Fig. 2(b)]. Grunberg recognized this, stating “It is clear that
this is an attractive aspect for appications, such as magnetoresistive field sensors” [6] and filing a patent [25].
fusion length. Camley and Barnas [30] then solved the
Boltzmann equation for up- and down-spin electrons for a F/N
structure in which a spin diffusion length could be defined for
the composite structure. This approach, similar to that of
Campbell and Fert, allowed for unique spin diffusive scattering
parameters and became the accepted formalism.
MARKET FORCES THAT SHAPE
TECHNOLOGY
From the data in Fig. 1, density trends for the semiconductor
and magnetic recording industries are quite similar, especially
since 1990. It is common to speculate that Moore’s law has
become a self-fulfilling prophecy. Technological trends are
driven by economic forces, and market trends for the two
industries are illustrated in Fig. 3. Global chip sales, representing inventory sales of semiconductor chips, are plotted from
1982 to 2006. These figures do not refer to finished products
such as computers, but only represent the chips themselves.
Roughly speaking, half of all chips are for information processing and half for memory. For the 24 year period plotted, revenues doubled about 4 times. The doubling time of 6 years is
longer than that of Moore’s law and indicates a benefit to the
consumer: costs have risen more slowly than performance, and
The MR of 1.5% was small, but closely related work reported
in epitaxially grown Fe / Cr multilayers [7] demonstrated that
large values of MR could be achieved. This report of “Giant
Magnetoresistance,” demonstrating MR of 80% at T = 4 K,
generated tremendous interest in the magnetism community.
Within two years, experiments on sputtered Co / Cu superlattices showed giant MR values of 65% at room temperature [26],
further demonstrating that high values of MR were not dependent on MBE growth. Parkin [27] also discovered oscillatory
exchange coupling in Co / Ru multilayers, developing a magnetic bias technique that is commonly used in all MR sensors.
The spin valve structure was quickly refined [12]. The MR
value in commercial spin valve sensors reached about 20% (at
the wafer level) in 2004, but MTJs already had TMR values of
40% or more.
Theoretically, Campbell and Fert introduced separate up- and
down-spin resistivities for conduction electrons in ferromagnetic materials with nonmagnetic impurities [28]. Silsbee introduced separate up- and down-spin resistivities [29] for both F
and N metals, in structures in which each had a unique spin dif-
Fig. 3
Market trends for the magnetic recording and semiconductor
information processing industries. The US gross domestic
product (GDP) is shown for comparison. Dollars are not
adjusted for inflation.
3/11/2008
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Page 22
GIANT MAGNETORESISTANCE ... (JOHNSON)
the average person can spend a few hundred dollars for a desktop computer with tremendous computing power.
Figure 3 also plots global hard disk drive (HDD) sales for a
similar time period. These figures represent the costs of entire
hard disk units, including disks, read/write head, electronics,
and packaging. HDD sales represent roughly half of the revenue of the magnetic recording industry. Comparing global
chip and HDD sales for 2006, about $260 B and $34 B, respectively, it is obvious that the semiconductor industry, and the
broader electronics industry, are much larger than the magnetic recording industry. Another observation is equally apparent.
The density of recorded information, the capacity of storage
systems, and the number of HDD units sold have all increased
dramatically, but not revenues: Increases in capacity and number of units have been offset by rapidly decreasing prices. The
cost of storage fell from $11.50 / MB in 1988 to $0.0004 / MB
in 2007, a decrease by a factor of 30,000 in twenty years. A
consumer today can purchase a $100 hard drive that fits in a
shirt pocket and stores 200 GB, equal to the capacity of 40,000
RAMAC systems, each of which weighed a ton.
The semiconductor industry has successfully broadened markets, constantly finding new applications. Chips are everywhere today, from toys to automobiles. The magnetic recording
industry, by contrast, has relied on the same markets, computers and stand-alone memory systems. That approach is now
changing. Micro-drives offer low cost and high capacity in a
package that can be used in mobile and consumer electronics.
By 2007, the number of HDDs sold for these new applications,
about 200 million, was greater than the entire number of HDD
units sold five years earlier [5].
However, the price of semiconductor nonvolatile memory also
has decreased dramatically. The cost of FLASH memory fell
from $0.0147 / MB in 2005 to just $0.0044 / MB in 2007, only
two years later. Sales of FLASH are expected to increase by a
factor of 25 between 2006 and 2010. FLASH memory has less
capacity, has a slower data transfer rate, and is more expensive
than micro-HDDs, but the access times are short. Consumer
electronics will be a battle ground between magnetics and
semiconductors, with tens of billions of dollars of sales at
stake.
One consequence is the rise of a new subfield of magnetism
called Magnetoelectronics or Spintronics. The goal is to combine unique qualities of magnetic materials, along with spindependent transport physics, with the architecture of integrated
electronics. Magnetoelectronics often refers to device families
using only metals. Daughton and Pohm, who developed an
integrated, magnetic random access memory (MRAM) based
on AMR devices [31], were early pioneers. Research and development have led to the commercial introduction of a nonvolatile MRAM chip based on MTJ cells [32]. Spintronics typically refers to an approach using spin-dependent transport of
carriers in semiconductors. While there has been tremendous
interest in the physics of magnetic semiconductors and semiconductor based devices [33], commercial applications are not
yet on the horizon. Although magnetoelectronics and spintronics have developed independently of the spin valve and GMR,
these subfields have benefited indirectly from research in magnetic materials.
CONCLUSION
The magnetic recording industry experienced a remarkable
paradigm shift with the introduction of MR read heads in 1991.
The MR architecture has adapted to three different archetype
devices, using AMR, GMR and TMR. Spin valve sensors were
employed for several years, and the legacy of GMR may be the
excitement and interest generated in the field of magnetism.
MTJs with MgO tunnel barriers [34] now have MR values of
400% [35], and MTJs will likely be the dominant magnetic
device for the next several years. Although it is based on different physical principles, the MTJ has benefited from materials
and processing advances that were motivated by spin valve
research.
REFERENCES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
J.S. Kilby, “Miniaturized Electronic Circuits,” US patent no. 3,138,743 (1964).
R.N. Noyce, “Semiconductor Device-and-Lead Structure,” US patent no. 2,981,877 (1961).
G.E. Moore, Electronics Magazine, 19 April, 1965.
Data points are available at the Intel Corp. web site, intel.com/technology/mooreslaw.
Personal communication, Tom Coughlin, Coughlin Associates.
G. Binasch, P. Grunberg, F. Saurenbach, and W. Zinn, “Enhanced magnetoresistance in layered magnetic structures with antiferromagnetic interlayer exchange,” Phys. Rev. B, 39, 4828 (1989).
M.N. Baibich et al., “Giant Magnetoresistance of (001)Fe/(001)Cr Magnetic Superlattices,” Phys. Rev. Lett., 61, 2472 (1988).
There have been numerous contributions to the development of the CMOS FET. See, for example, F. Wanlass and C.-T. Sah, US patent
no. 3,355,858 (1963); C.A. Mead, Proceedings of the IEEE, 54 (2), 307-308 (1966).
O. Smith, Electrical World, Aug. 9, 1888.
R.D. Hempstead et al., US patent 4,103,315 (1978).
R.P. Hunt, US patent 3,493,694 (1970).
B. Dieny et al., J. Appl. Phys., 69, 4774 (1991).
A. Fert and P. Bruno, Ultrathin Magnetic Structures II, Eds. B. Heinrich and J.A.C. Bland, (Springer-Verlag, Berlin 1994); chapter 2.2.
S.X. Wang and A.M. Taratorin, Magnetic Information Storage Technology, (Elsevier, Oxford 1999).
22 C PHYSICS
IN
3/11/2008
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Page 23
GIANT MAGNETORESISTANCE ... (JOHNSON)AA
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
N.F. Mott, “The Electrical Conductivity of Transition Metals,” Proc. Roy. Soc. A, 153, 699 (1936).
P.M. Tedrow and R. Meservey, Phys. Rev. Lett., 26, 191 (1971).
M. Julliere, Phys. Lett., 54, 225 (1975).
A.G. Aronov, JETP Lett., 24, 32 (1976).
R.H. Silsbee, Bull. Mag. Res., 2, 284 (1980).
Mark Johnson and R. H. Silsbee, Phys. Rev. Lett., 55, (1985).
W.H. Meiklejohn and C.P. Bean, Phys. Rev., 102, 1413 (1956).
L.L. Hinchey and D.L. Mills, Phys. Rev. B, 33, 3329 (1986).
C.F. Majkrzak et al., Phys. Rev. Lett., 56, 2700 (1986).
For example: P. Swiatek, F. Saurenbach, Y. Pang, P. Grunberg und W. Zinn, J. Appl. Phys., 61, 3753-3755 (1987).
P. Grunberg, “Magnetic field sensor with ferromagnetic thin layers having magnetically antiparallel polarized components,” US patent
4,949,039 (1990).
S.S.P. Parkin et al., Phys. Rev. Lett., 66, 2152 (1991)
S.S.P. Parkin, N. More and K.P. Roche, Phys. Rev. Lett., 63, 2304 (1990).
A. Fert and I.A. Campbell, J.Phys. F, 6, 849 (1976).
Mark Johnson and R.H. Silsbee, Phys. Rev. B, 37, 5312 (1988).
R.E. Camley and J. Barnas, Phys. Rev. Lett., 63, 664 (1989).
A.V. Pohm et al., IEEE Trans. Magn., 24, 3117 (1988).
R.W. Dave et al., IEEE Trans. Magn., 42, 1935 (2006).
E.I. Rashba, Physics in Canada, 63 (2), 61 (2007).
W.H. Butler et al., Phys. Rev. B, 63, 054416 (2001).
S. Yuasa et al., Appl. Phys. Lett., 89, 042505 (2006).
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FEATURE ARTICLE
In 2005, the Division of Nuclear Physics (DNP) created a PhD Thesis Prize competition for best thesis in Experimental or Theoretial Nuclear Physics by any
student receiving their PhD degree from a Canadian University in the current or prior calendar year. The DNP is pleased to announce that the recipient of the
2007 DNP Thesis Prize is Simon Turbide. Dr. Turbide was awarded his PhD by McGill University in 2006 for the work “Electromagnetic radiation from matter
under extreme conditions”. A summary of Dr. Turbide’s thesis work appears below.
PHOTON PRODUCTION FROM RELATIVISTIC
HEAVY ION COLLISIONS
BY
SIMON TURBIDE*
I
t has been expected that hadronic matter might dramatically change its properties at finite temperature
and density. The quest of understanding the behaviour of nuclear matter under extremely high density
and temperature has been one of the main goals of nuclear
physicists for decades. This field of research is important
for two reasons. Firstly, from a fundamental point of view,
it is interesting to know what happens when ordinary matter is subjected to very high temperatures and/or densities,
and secondly, this knowledge is essential to explain the
behaviour and characteristics of astrophysical bodies, like
neutron stars and supernovae, since their interior is
expected to be made of such matter.
In order to reach a deeper understanding of the physics
involved in these phenomena, elaboration of theoretical
models and their confirmation by experimental measurements are needed. As the astrophysical bodies are not at
hand, being too distant and too rare, one has to find a substitute on earth for these phenomena. The only known candidate is heavy-ion collisions.
Simon Turbide
<simon.turbide@
mail.mcgill.ca>,
Department of
Physics, McGill
University, Montréal,
QC, H3A 2T8
The hadrons are not fundamental particles: they are made
of quarks, which interact through gluon exchange. The
fundamental theory describing their interactions is
Quantum Chromodynamics (QCD) [1], which predicts the
confinement of quarks inside hadrons at zero temperature.
However, in the early 1980’s, it was suggested that
SUMMARY
The hot and dense strongly interacting matter created in collisions of heavy nuclei at
Relativistic Heavy Ion Collider (RHIC) energies is modeled with relativistic hydrodynamics, and the spectra of photons produced in these events are calculated. Several
different sources are considered, and their
relative importance compared, showing the
importance of the quark-gluon plasma (QGP)
contribution, while the sum of all contributions is in good agreement with recent
experimental results from PHENIX
* Present address:
RDDC Valcartier,
2459 Pie-XI Nord,
Val-Belair, QC, G3J
1X5
24 C PHYSICS
IN
hadrons would overlap at sufficiently high energy density
and that the constituents of hadrons would move rather
freely over the confinement range. This expected phase of
quarks and gluons has been called the quark-gluon plasma
(QGP) [2].
While the QGP in the standard cosmological model prevailed until some micro-seconds after the Big-Bang, it
could also be produced during a shorter time-scale in the
aforementioned relativistic collisions of heavy ions (see
Ref. [3] for a review). The quest for the QGP is a real challenge, since the QGP is not a final state. Its’ evaluated lifetime in heavy ion collisions is some fm/c, and its experimental detection involves not directly the partons (quarks
and gluons), but the hadrons produced during and after the
phase transition, when quarks convert to hadrons.
However, even if we cannot see directly the QGP, there
exists detectable particles, which can probe this early
phase: the photons.
As photons interact only electromagnetically with the surrounding matter, they have the potential to probe the
detailed dynamical history of high energy heavy ion collisions. Their mean free path inside the hot and dense medium being much larger that its typical size, the photons will
in principle leave the interacting zone without rescattering, reflecting directly the properties of the medium at the
time they have been produced. This is why the photon is
probably the most important tool for probing the QGP.
In the experimental detection of photons produced during
the relativistic heavy-ion collisions, the QGP contribution
may be hidden, or have its effect reduced by the sum of all
other sources. It is thus essential to have robust calculations for these contributions, which can be cast into four
categories. The first category includes the (prompt) photons produced during the overlap of the two nuclei and
before thermalization is reached. The second category
includes the photons produced during the QGP phase,
while the photons produced during the subsequent hadronic phase belongs to the third category. Finally, the decay of
neutral mesons like π0, after the freeze-out [4], will also
contribute to the photon yield and belongs to the last category. This last contribution, which constitutes the back-
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ARTICLE DE FONDAA
ground for the photon yield, can be subtracted experimentally,
leaving, after subtraction, the so-called direct production of
photons. I present in this paper a summary of my Ph.D work on
high-pT direct photons at RHIC energies, where pT denotes the
photon’s momentum transverse to the collision axis. The heavy
ion collision studied here is Au-Au, with a center of mass energy /s = 200 GeV per pair of colliding nucleons.
The prompt photon contribution can be divided into two subcategories: the photons produced by the direct processes, such
as for example q + g 6 q + γ, and the fragmentation contribution, such as q + g 6 qjet + gjet followed by the fragmentation
of qjet or gjet into photons. While q and g represent the incoming partons (quarks, antiquarks and gluons), qjet and gjet stand
for jets, which means partons produced with high transverse
momentum. For high momentum exchange processes, the
prompt-direct contribution can be evaluated as a superposition
of proton-proton (p - p) collisions:
dN
Au − Au
prompt − direct
2
dyd pT
= ncoll
dN
p− p
prompt − direct
dyd 2 pT
,
(1)
where ncoll represents the average number of binary p-p collisions in a Au-Au collision. However, the fragmentation contribution may suffer final state effects. Indeed, the jets produced
may be “quenched”, losing some fraction of their energy by
going through the QGP before fragmenting into photons. We
have used the formalism developed by Arnold, Moore and
Yaffe (AMY) [5], which describes the jet-quenching as a
bremsstrahlung emission of gluons from jets. The only free
parameter of their formalism is the strong coupling constant αs.
Since neutral pions are expected to mainly originate from a jetfragmentation mechanism [6], we have used π0 data to fix αs.
The high-pT data in a Au-Au collision can be characterized by
the nuclear modification factor:
RAA =
dN πAu0 − Au / dyd 2 pT
ncoll dnπp0− p , dyd 2 pT
.
(2)
In the absence of final state effects, RAA would be consistent
with one. In the other limit, it will approach zero if the jets are
fully stopped by the surrounding matter. In Fig. 1 is shown our
results for the nuclear modification factor of neutral pions,
evaluated in the AMY formalism for different values of the
strong coupling constant. We took αs = 0.3 as an effective
value for the strong coupling constant in the QGP.
The radiation coming from the QGP is evaluated by integrating
the photon production rate over space and time. The photon
production rates in the QGP, used for that work, were also
taken from the AMY formalism [5]. The initial geometry of the
QGP is provided by the overlap of the two nuclei, and the subsequent space-time evolution of the QGP follows hydrodynamical equations for a non-viscous fluid. It has been suggested by
Fries et al. in Ref. [8] that the primordial jets produced during
Fig. 1
The production of energetic pions originates from the fragmentation of jets (fast partons) created during the first
moments of a relativistic heavy-ion collision. A good probe to
evaluate the level of density reached is the nuclear modification factor RAA. In the limit where the reaction consists of the
simple superposition of individual proton-proton collisions,
all jets escape the colliding zone and RAA = 1. On the other
hand, if the matter density after the collision is so high that all
jets are stopped before fragmenting into pions, then RAA = 0.
We show in this figure our RAA calculations for different
effective values of the strong coupling constant. The results
are compared with experimental data from PHENIX [7]. The
low value, RAA ~ 0.3, indicates evidence of jet-quenching,
and thus, the formation of matter at high density.
the first instance of the collisions, could also, while propagating into the QGP, produce high-pT direct photons. Following
their work, we have investigated the effect of jet-quenching on
this contribution, and show that despite the suppression caused
by the induced bremsstrahlung in the medium, the jet-QGP
contribution is still a major source of photons between 2 and
4 GeV, as seen in Fig. 2.
Finally, to complete the theoretical evaluation of the direct photon yield in heavy ion collisions, we have evaluated the photon
yield coming from the hadron gas phase. The interaction of
hadrons is not perturbative in a QCD context, such that the corresponding cross-sections cannot be obtained from a finite
number of Feynman diagrams involving quarks and gluons.
Instead, effective theories are used, with hadrons as the degree
of freedom. It is essential that such a theory respects the symmetries of QCD. The chiral Symmetry is perfectly respected in
QCD with massless quarks. We know, however, that quarks are
not massless (light quarks are about 5-10 MeV), and since the
relevant energy scale is given by ΛQCD 200 MeV, we expect the
chiral currents to be approximately conserved. We have
extended previous analysis based on chiral Lagrangians,
including strangeness and form factors, which take care of
finite-size effects. Adjusting consistently the coupling constants of the chiral Lagrangian and the form-factors, with measured values of meson masses and decay widths, we have also
3/11/2008
12:04 PM
Page 26
PHOTON PRODUCTION ... (TURBIDE)
hadronic production rates over space and time, we found that
the hadronic contribution was however subdominant in the
range of transverse momentum covered by the data, except
around pT = 1 GeV. While the yield above pT = 4 GeV seems
dominated by the prompt contribution, the data in the window
2 < pT < 4 GeV can only be successfully reproduced, in our calculations, by the inclusion of QGP contributions, particularly
the jet-QGP contribution.
Fig. 2
Electromagnetic radiation from high-energy collisions of
heavy ions has the potential to directly probe the high temperature and high density phases of these reactions. This is
because photons suffer few final state interactions. In this figure is shown our calculations for the total yield of direct photons in central Au-Au collisions at RHIC. Included are the
hadron gas (dotted line), jet-QGP (dashed line), the prompt
(dot-dashed line), the thermal radiation from QGP (double
dot-dashed line), and the sum of all contributions (solid line).
The results are compared to experimental measurements
from PHENIX [9]. The good agreement, along with the
importance of the QGP processes, strongly suggests the formation of a QGP phase at RHIC.
highlighted the importance of new channels, as mesons collisions with the exchange of ω mesons. After integration of our
While it is perhaps too soon to claim the undeniable existence
of a quark-gluon plasma, these results constitute a definite step
in that direction and do point to the existence of new physics.
The continuing program at RHIC will greatly contribute to put
these results on an even firmer quantitative basis. In addition,
in the very near future results from the heavy ion program at
the Large Hadron Collider (LHC), with a center of mass energy 30 times higher that RHIC’s, will shine a new light on all
these issues, and has the potential to strongly reinforce all evidence on the new state of matter discovered at RHIC. The relativistic nuclear collision program being pursed at major facilities around the world (RHIC, LHC, and FAIR) will continue
to provide fascinating data on the QCD phase diagram for
years to come.
ACKNOWLEDGEMENTS
I would like to express my sincere thanks to my supervisor,
Professor Charles Gale, for all the help necessary for the completion of my Ph.D degree. This work was supported in part by
the Natural Sciences and Engineering Research Council of
Canada, and in part by McGill University.
REFERENCES
1. M.E. Peskin and D.V. Schroeder, An Introduction to Quantum Field Theory, Ed. Perseus Books, 1995, 842 p.
2. E.V. Shuryak, Phys. Rept., 61 (1980) 71.
3. K. Adcox et al. [PHENIX Collaboration], Nucl. Phys. A, 757, 184 (2005) [arXiv:nucl-ex/0410003].
4. The freeze-out is defined by the moment at which the hadronic matter becomes so dilute that the average distance between hadrons
exceeds the range of the strong interactions. At this point, all scatterings stop and hadrons decouple.
5. P. Arnold, G.D. Moore and L. Yaffe, JHEP , 057 (2001); JHEP , 030 (2002).
6. R.J. Fries, B. Müller, C. Nonaka and S.A. Bass, Phys. Rev. C , 044902 (2003).
7. S.S. Adler et al., Phys. Rev. Lett. , 072301 (2003).
8. R.J. Fries, B. Müller and D.K. Srivastava, Phys. Rev. Lett , 132301 (2003).
9. H. Büsching (for the PHENIX Collaboration), Nucl. Phys. A , 103 (2006).
26 C PHYSICS
IN
3/11/2008
12:04 PM
Page 27
DOCTORATS DÉCERNÉS
PHD PHYSICS DEGREES AWARDED IN CANADIAN UNIVERSITIES
DOCTORATS EN PHYSIQUE DÉCERNÉS AUX UNIVERSITÉS CANADIENNES
DECEMBER 2006 TO NOVEMBER 2007 / DÉCEMBRE 2006 À NOVEMBRE 2007
CARLETON UNIVERSITY
GHASSRODDASHTI, E., "Predicting Respiratory
Induced Tumor Motion Using External
Surrogates", (L. Gerig), May 2007, now a
Medical Physics Resident with the London
Health Science Centre.
NKONGCHU, K., "Magnetic Resonance Imaging
Approaches to Gel Dosimetry for Validation of
Conformal Radiotherapy Treatment Plans",
(G. Santyr), February 2007, now a Diagnostic
Physics Resident at the Henry Ford Hospital in
Detroit, Michigan.
ECOLE POLYTECHNIQUE
AGUIRRE-CARMONA, C., «Carbon nanotube
networks
for
organic
electronics»,
(P. Desjardins, directeur), (R. Martel , codirecteur), présenté 2007 décembre 19, diplômé
octroyé 2007 automne.
ASSAWAROONGRUENGCHOT, M., «Application of Perturbation Theory to Lattice
Calculations Based on Method of Cyclic
Characteristics», (G. Marleau, directeur),
(J. Koclas, codirecteur), présenté 2007 août 07,
diplôme octroyé 2007 septembre 24, 2007 été.
ÖZCAN, L.-Ç., «Écriture directe de circuits
optiques planaires dans des couches minces de
silice sur silicium par ablation au laser CO2»,
(R. Kashyap, directeur), (L. Martinu, codirecteur), présenté 2007 décembre 18, diplômé
octroyé 2007 automne.
ZHANG, G., «Studies on metal catalysts and carbon
materials for fuel cell applications», (E. Sacher,
directeur), (J.-P. Dodelet, codirecteur), présenté
2007 novembre 28, diplôme octroyé 2007
automne.
HASSANI, Khosrow, “X-ray microdiffraction
techniques to study the microstructure of materials”, (M. Sutton), October 2007, Assistant
Professor, Physics Department, University of
Tehran, Iran
HESSELS, Jason, “Discovery and study of exotic
radio pulsars”, (V. Kaspi), May 2007,
Postdoctoral Fellow at Astronomical Institute
“Anton Pannekoek”, Amsterdam
JARRY, Genevieve, “Study of novel techniques for
verification imaging and patient dose reconstruction in external beam radiation therapy”,
(F. Verhaegen), May 2007, plans unknown
LINDNER, Thomas, “STACEE observations of
BL Lac objects”, (D. Hanna), May 2007,
Postdoctoral Fellow at University of British
Colombia
LIU, Chuanlei, “Neutral strangeness production
with the ZEUS detector at HERA”,
(F. Corriveau), May 2007, Research Associate
at the University of Carleton
MARTINEAU, Patrick, “Topics in cosmological
flucturations: linear order and beyond”,
(R. Brandenberger),
October
2007,
Postdoctoral Fellow at McGill, Physiology
Department
SHUHMAHER, Natalia, “Aspects of cosmology
from particle physics beyond the standard
model”, (R. Brandenberger), October 2007,
Postdoctoral Fellow at Univeristy of Geneva,
Theoretical Physics Department, Switzerland
STEWART, Kristin, “The development of new
devices for accurate radiation does measurement: A guarded liquid ionization chamber and
an electron”, (J. Seuntjens), October 2007,
plans unknown
WALDRON, Derek, “Ab-initio simulation of spintronic devices”, (H. Guo), October 2007,
Consultant, McKinsey and Company, Montreal
MCGILL UNIVERSITY
MCMASTER UNIVERSITY
AL-YAHYA, Khalid Sulaiman, “Energy modulated electron therapy; design, implementation,
and evaluation of a novel method of treatment
planning and delivery”, (J. Seuntjens), May
2007, plans unknown
NERETINA, S., “The Deposition of CDTE Using
Exotic Growth Pathways.”,(P. Mascher),
August 2007, now Post Doctoral Fellow at
Georgia Tech, Atlanta
BARNABY, Neil, “Cosmological instabilities”,
(J. Cline), October 2007, Postdoctoral Fellow
at CITA, University of Toronto
DIAS, Cristiano, “Models of the stability of proteins”, (M. Grant), October 2007, Postdoctoral
Fellow at the University of Western Ontario,
Department of Applied Mathematics, London,
Ontario
GAGNON, Jean-Sebastien, “Leading order calculation of transport coeffiecients in hot quantum
electrodynamics from diagrammatic methods”,
(S. Jeon), October 2007, Postdoctoral Fellow at
the University of Lausanne in Switzerland
MEMORIAL UNIVERSITY
KENNEDY, Kristi, “Fingering Instabilities in
Newtonian and Non-Newtonian Fluids”, (J. de
Bruyn), May 2007, status unknown.
QUEEN’S UNIVERSITY
DÉMORÉ, C., "Design of Ultrasound Transducer
Arrays for Medical Imaging", (G. Lockwood),
May, 2007, now post doc in the School of
Engineering, Physics and Mathematics at the
University of Dundee, UK
SUSSMAN, B., “Quantum Control using the NonResonant Dynamic Stark Effect,” (A. Stolow /
J. Fraser), May 2007, now post doc in the
Department of Physics at the University of
Oxford, UK
UNIVERSITÉ DE MONTRÉAL
BRUNET, S., « Mesure du rapport d’embranchement DEB-> PIO L V et extraction de l’élément
VUB de la matrice CKM à l’expérience
BABAR à l’aide de la technique des étiquettes.
», (P. Taras), 2007 juin. Maintenant boursière
postdoctoral, DESY, Allemagne.
CHENÉ, A.-N., « Mesure du taux de rotation des
étoiles WOLF-RAYET à partir de la variabililté
périodique à grande échelle des vents stellaires
», (N. St-Louis), 2007 décembre. Maintenant
boursier postdoctoral, Herzberg Institute,
Victoria, B.C.
DUFOUR, P., « Étude de l’évolution spectrale des
étoiles naines blanches froides riches en hélium
: analyse spectroscopique et photométrique des
étoiles de type DQ et DZ », (P. Bergeron), 2007
février. Maintenant boursier postdoctoral,
Stuart Observatory, Tucson, AZ, USA.
FORTIER, M. , « Étude biophysique des facteurs
influençant l’activité des toxines du bacille de
THURINGE. », (R. Laprade), 2007 janvier.
Maintenant conseillère en génie biomédical,
Groupe Biomédical Montérégie, St-Hubert,
Québec.
CZABAN, J., “Impact of Composition Modulation
and Metamorphic Substrates on Tensile
Strained InGaAs QWs for Long-Wavelength
Semiconductor Optical Amplifiers.” (D.A.
Thompson), September 2007, now Post
Doctoral Fellow at McMaster, Hamilton
GAGNON, D., « Étude des changements de conformation du cotransporteur de NA+/Glucose
(SGLT1) à l’aide de mesures électrophysiologiques et de marqueurs fluorescents », (J.-Y.
Lapointe), 2007 janvier. Maintenant boursière
postdoctoral à l’Université de Chigaco,
Chicago, Il., USA
YANG, J., “Sensitivity enhanced long-period fiber
grating based photonic devices for biochemical
sensing.” (C.Q. Xu), October 2007, now Post
Doctoral Fellow at McMaster, Hamilton
GENEST, M.-H., « Recherche du neutralino avec
les détecteurs ATLAS et PICASSO » (C.
Leroy), 2007 août. Maintenant boursière postdoctoral à Munich, Allemagne.
LAFRENIÈRE, D., « Relevé des planètes géantes
autour d’étoiles proches par imagerie directe et
optimisation d’une technique d’imagerie multi-
3/11/2008
12:04 PM
Page 28
DEGREES AWARDED
bandes. » (R.Doyon et D. Nadeau), 2007 octobre. Maintenant boursier à l’Université de
Toronto, Toronto, Ont.
PEREZ, D., « Effets des contraintes élastiques sur
la cinétique de séparation de phases dans les
alliages. » (L. J. Lewis) 2007 février.
Maintenant boursier à Los Alamos National
Laboratory, NM., USA
UNIVERSITÉ DE
SHERBROOKE
DENOYER, A., « Études optiques de nouveaux
matériaux laser: des orthosilicates dopés à
l'Ytterbium Yb:Y(Lu,Sc)2SiO5 », (S. Jandl),
avril 2007. Maintenant professionnelle
d’ingénierie en gravure chez Dalsa
Semiconducteur à Bromont (Québec).
DUPONT, É., « Transport de paires EPR dans les
structures mésoscopiques », (K. Le Hur), janvier 2007. Maintenant attachée temporaire d'enseignement et de recherche (ATER) à
l’Université Pierre et Marie Curie à Paris
(France).
FOURNIER D., « Compétition entre supraconductivité et magnétisme au voisinage de la transition de Mott dans le conducteur organique
quasi-bidimensionnel
κ-(BEDT-TTF)2Cu
[N(CN)2]Br », (M. Poirier), mars 2007.
Maintenant stagiaire postdoctoral à l’Université
de la Colombie-Britannique (UBC).
ROY, S., « Le modèle du Hubbard bidimensionnel à
faible couplage : thermodynamique et
phénomènes critiques », (A.-M. Tremblay),
septembre 2007. Maintenant stagiaire posdoctoral à l’Université de Sherbrooke.
UNIVERSITÉ DU QUÉBEC À
TROIS-RIVIÈRES
LAURENCELLE, François,"Développement d’un
compresseur d’hydrogène basé sur le cyclage
thermique des hydrures métalliques", (Jacques
Goyette), août 2007.
POIRIER, Éric,"Étude du stockage de l'hydrogène
sur des nanostructures de carbone microporeuses", (Richard Chahine), Janvier 2007.
UNIVERSITÉ LAVAL
BRETON, M., "Détection de l’allumage d’un
moteur-fusée à propergol solide avec une
matrice linéaire de filtres holographiques et par
diffraction conique", (R.A. Lessard, J. Fortin),
2007 novembre, RDDC-Valcartier, Québec.
EDWARDS, L., "Line Emission in Brightest
Cluster Galaxies : The Nature of Recent
Activity", (C. Robert), 2007 décembre.
Postdoctorat à Trent University.
GAJADHARSINGH, A.K., "Application de la
méthode des moments pour l'étude de la propagation non-linéaire d'impulsions dans une fibre
optique", (P.A. Bélanger), 2006 septembre.
HARBOUR, S., "Étude dynamique et structurelle
d'un matériau H-PDLC sensible dans le proche
IR", (T. Galstian), 2007 août. Consultant LCI,
Qc
28 C PHYSICS
IN
NGUYEN, T.N.T., "Étude des changements
optiques et structuraux dans les verres induits
par laser TI : saphir", (R. Vallée), 2006 décembre
UNIVERSITY OF BRITISH
COLUMBIA
ROUSSEAU, G., "Étude des faisceaux laser et des
impulsions brèves à symétrie cylindrique", (M.
Piché), 2006 octobre.
BERGMAN, A., “Monte Carlo simulation of x-ray
dose distributions for direct aperture optimization of intensity modulated treatment fields”,
(Grein, Ellen), May 2007.
ROY, V., "Lasers à fibre à synchronisation modale
passive par rotation nonlinéaire de la polarisation. Dynamique en régime multi-impulsionnel", (M. Piché), 2007 août, INO, Québec
THÉBERGE, F., "Third-order parametric processes during the filamentation of ultrashort laser
pulses in gases", (S.L. Chin), 2007 avril.
Postdoctorat, RDDC-Valcartier, Québec.
VARFALVY, N., "Fluorescence dispersée et induite
par laser et spectrométrie à transformée de
Fourier : analyse rovibronique des premières
polyades du 12CO2+", (D. Roy), 2007 août.
Physicien médical, CHUQ Hôtel-Dieu de
Québec.
VARIN, C., "Impulsions d'électrons relativistes
ultrarapides à l'aide d'un schéma d'accélération
par laser dans le vide", (M. Piché), 2006 septembre.
UNIVERSITY OF ALBERTA
GOMEZ PEREZ, Natalia, "Planetary Magnetic
Fields in the Solar System: A Numerical Study
of Dynamo Models", (Moritz Heimpel)
September 2007, Postdoctoral fellow in the
Department of Terrestrial Magnetism, Carnegie
Institution, Washington DC.
HRYCIW, Aaron, "Optical properties of rare-earthdoped silicon nanocomposites", (Al Meldrum)
January 2007, NSERC postdoctoral fellowship
at Stanford University, winner of the Governor
General's Gold Medal.
LIU, Zhigang, "Magnetization dynamics in the
presence of nanoscale spatial inhomogeneity",
(Mark Freeman & Rick Sydora) September
2007, Postdoctoral fellow at UC Santa Cruz.
MARSH, Rebeccah, "Deterministic and Stochastic
Models of Drug Transport and Reaction
Kinetics in Heterogeneous Media", (Jack
Tuszynski), January 2007, Program Director at
MITACS at Simon Fraser University.
MONAJEMI, Thalat Theresa, "Cadmium
Tungstate Scintillators in Contact with Silicon
Photodiodes as Detectors for Megavoltage
Computed Tomography", (Gino Fallone and
Satyapal Rathee) May 2007, Medical Physicist
at the Cross Cancer Institute, Edmonton, AB.
SCHINKEL, Colleen, "Clinical applications of
TCP and NTCP models: Incorporation of NTCP
models into modern inverse planning optimization and investigation of the applicability of
population-averaged and non-averaged TCP
models for the purpose of parameter estimation" (Gino Fallone), August 2007, Medical
Physicist at the Anderson Cancer Center at the
University of Texas in Houston Texas.
THOMAS, Steven, "Dose Verification in ImageGuided Adaptive Radiotherapy" (Gino Fallone)
June 2007, Medical Physicist with the BC
Cancer Agency.
LING, H., “Generally covariant actions for multiple
DO-branes”, (Van Raamsdonk, Mark),
November /2007.
McCUTCHEON, M., “Nonlinear Optics of Multimode Planar Photonic Crystal Microcavities”,
(Young, Jeff), November 2007.
POINTON, B., “Model-Based Randoms Correction
for 3D Positron Emission Tomography”, (Sossi,
Vesna), May 2007.
YOUNG, D., “The AdS/CFT Correspondence: classical, quantum, and Thermodynamical”,
(Semenoff, Gordon), November 2007.
CHANG, M., “The Stripe Phase in 4-Leg Ladders
and Quantum Impurity Entanglement”,
(Affleck, Ian), November 2007.
POPE, A., “The role of submillimetre galaxies in
galaxy evolution”, (Scott, Douglas), November
2007.
UNIVERSITY OF GUELPH
DE HAAN, H., “Nonequilibrium Molecular
Dynamics Calculation of the Conductance of
the KcsA Potassium Ion Channel”, (Supervisor:
C. Gray), April 25, 2007, now a Post Doctoral
Fellow at the Department of Physics,
University of Ottawa
GRINYER, G., “High-Precision Half-life Measurements for Superallowed Fermi ß Decays”,
(Supervisor: C. Svensson), November 28, 2007,
now a Post Doctoral Fellow at the National
Superconducting Cyclotron Laboratory at
Michigan State University, recipient of
Gerger’s Hansen Fellowship
MURRAY, C., “The Effects of Heating and
Chemical Acetylationon Ultrathin Chitosan
Films”, (Supervisor: J. Dutcher), April 20,
2007, now working at Monteco an engineering
firm in Mississauga in research and development.
UNIVERSITY OF MANITOBA
BLAND, J., "Dimension Dependence of the Critical
Phenomena in Gravitational Collapse of
Massless Scalar Field" (G. Kunstatter) May
2007.
ZHANG, J., "Dynamic NMR Studies of molecular
Motions and Order in Calamitic and Discotic
Liquid Crystals" (R. Dong) October 2007.
VAN UYTVEN, E., "3D Electron Density Imaging
Using Single Scattered X-rays with Application
to Breast CT and Mammographic Screening"
(S. Pistorius) May 2007.
3/11/2008
12:04 PM
Page 29
DOCTORATS DÉCERNÉES
UNIVERSITY OF OTTAWA
SMELSER, CHRISTOPHER, “Ultrafast Infrared
Laser Fabrication of Fiber Bragg Gratings with
a Phase Mask” (S. Mihailov) January 2007, currently a research scientist with the
Communications Research Centre Canada .
KENWARD, MARTIN, “On the Simulation and
Theory of Polymer Dynamics in Sieving
Media: Friction, Molecular Pulleys, Brownian
Ratchets and Polymer Scission” (G. Slater)
March 2007, currently a Postdoctoral Fellow in
Chemical Engineering and Materials Science at
the University of Minnesota .
AWIROTHANANON, SUNIDA, “The electronic
structure of In As/GaAs Self-Assembled quantum dots in a magnetic field” (S. Fafard), April
2007, current employment not known.
FLACAU, ROXANA IOANA, “Structural and
Electron Density Changes in Dense Guest-Host
Systems: Analysis of X-ray Diffraction Data by
the Rietveld and Maximum Entropy Methods”
(S. Desgreniers/J.S. Tse) July 2007, currently
an NSERC Visiting Fellow at the NRC Steacy
Institute for Molecular Science in Ottawa.
RAVET, FABIEN, “Performance of the Distributed
Brillouin Sensor: Benefits and Penalties Due to
Pump Depletion” (X. Bao/L. Chen) August
2007, currently a research scientist with
Omnsens Inc in Switzerland.
GAUTHIER, MICHEL, “Simulation of Polymer
Translocation Through Small Channels: a
Molecular Dynamics Study and a New Monte
Carlo Approach” (G. Slater) November 2007,
currently an NSERC Postdoctoral Fellow,
Department of Physics, Simon Fraser
University.
UNIVERSITY OF
SASKATCHEWAN
MacNAUGTON, J., “Electronic Structure of DNA
and Related Biomaterials”, (A. Moewes),
October 2006, now Postdoctoral NSERC fellow
at Stanford University, California, USA.
SYDORENKO, D., “Particle in Cell Simulations of
Electron Dynamics in Low Pressure Discharges
with Magnetic Fields”, (A. Smolyakov),
October 2006, now Post-Doctoral Fellow the
University of Alberta, Edmonton, AB.
CHSHYOLKOVA, T., “Planetary Waves and
Dynamical Processes Associated with Seasonal
Atmospheric Disturbances”, (A. Manson), May
2007, now Post-Doctoral Fellow, Institute of
Space and Atmospheric Studies, University of
Saskatchewan.
CHEN, W., “Synthesis of Carbon and Tungsten
Based Thin Films by Plasma Enhanced
Chemical Vapor Deposition”, (A. Hirose /
C. Xiao), October 2007, now Post-Doctoral
Fellow,
Risoe
National
Laboratory,
Copenhagen, Denmark
BOURASSA, A., “Stratspheric Aerosol Retrieval
from OSIRIS Limb Scattered Sunlight
Spectra”, (D. Degenstein/E.J. Llewellyn),
October 2007, now Post-Doctoral Fellow,
NASA, Langley
LIU, Dazhi, “Vertical Compact Torus Injection into
the STOR-M Tokamak”, (A. Hirose), May
2007, now NSERC-JSPS Post-Doctoral Fellow,
Hyogo University, Himeji, Japan
Injection, Applied Current, and Magnetic
Field”, (J.Y.T. Wei), November 2007, now PDF
in the Applied Physics Department, Yale
University, USA.
LU, X., “Field Electron Emission from Diamond
and Related Films Synthesized by Plasma
Enhanced Chemical Vapor Deposition”,
(C. Xiao/A. Hirose), May 2007, now NSERC
Post-Doctoral Fellow, Department of Physics,
UBC.
NOROUZIAN, N., “Patch Template Correlation
(PTC) as a Method for AVO/AVA Analysis”,
(G.F. West), March 2007, now a Risk Analyst in
financial industry.
UNIVERSITY OF TORONTO
CODOBAN, S., “Available Energy of Symmetric
Circulations with Application to the Middle
Atmosphere”, (T.G. Shepherd), November
2007, now PDF with Professor Shepherd,
Department of Physics, University of Toronto.
DARADICH, A.L., “Dynamic Topography of
Continents and Rotational Stability of Planets
with Lithospheres”, (J.X. Mitrovica),
November 2007, currently raising a baby.
PASCALE,
E., “The Balloon-Borne Large
Aperture Submillimeter Telescope: BLAST”,
(C.B. Netterfield), November 2007, now a
Lecturer at Cardiff University, School of
Physics and Astronomy, U.K.
RAMAZANOGLU, M.K., “Phase Transitions in
Liquid Crystal + Aerosil Gels”, (R. Birgeneau),
June 2007, now PDF in the Physics and
Astronomy Department, McMaster University,
ON.
TSAI, P.A., “The Route to Chaos and Turbulence in
Annular Electroconvection”, (S.W. Morris),
November 2007, now PDF at University of
Twente, The Netherlands.
FOX KANEM, J., “Quantum State Manipulation
and Quantum Chaos in an Optical Lattice”,
(A.E. Steinberg), March 2007, now
Postdoctoral Research Scientist at Imperial
College, U.K.
VOLLRATH, I.E., “Measurement of the W Boson
Mass at the Collider Detector at Fermilab from
a Fit to the Transverse Momentum Spectrum of
the Muon”, (W. Trischuk), June 2007, now a
Quantitative Analyst for a financial software
company.
KENDALL, R.A.V.S., “Sea-Level Change on an
Ice-Age Earth: Theory, Algorithm and
Applications”, (J.X. Mitrovica), March 2007,
now PDF with Professor Mitrovica,
Department of Physics, University of Toronto,
ON.
WUNCH, D.B., “Measurements and Data Analysis
from a Balloon-Borne Fourier Transform
Spectrometer”, (J.R. Drummond), June 2007,
now PDF Environmental Science at California
Institute of Technology, USA.
KERACHIAN, Y., “Coherent Control of Charge
Currents, Spin Currents and Carrier Density in
Bulk GaAs”, (H.M. van Driel), June 2007,
Technology Transfer Officer, Wilfrid Laurier
University, Waterloo, ON.
LAI, S.T., “Search for Standard Model Higgs Boson
Produced in Association with a Top Anti-Top
Quark Pair in 1.96 TeV Proton-Antiproton
Collision”, (P.K. Sinervo), March 2007, now
PDF at University of Freiburg, Germany.
L’HEUREUX, E.C., “Investigation into the
Scattering Response of Mineral Ore Deposits in
Heterogeneous Environments by Means of 2D
and 3D Seismic Modelling”, (B.M. Milkereit),
November 2007, employed in oil industry.
MARTENS, F.K., “Method for Measuring CP
Violation in Top Quark Pair Production at
ATLAS”, ( R.S. Orr), November 2007, looking
for employment.
MOHSENI, M., “Characterization and Decoherence Control of Open Quantum Systems”,
(D. Lidar), June 2007, PDF at the Department
of Chemistry, Harvard University, USA.
NEDELJKOVIC, S., “TREX: A Small Antenna RF
Spectrometer”, (C.B. Netterfield), November
2007, now Computer System Engineer,
MotionDSP, USA.
NEEF, L.J., “Balance Dynamics and Gravity Waves
in Four-Dimensional Data Assimilation”, (T.G.
Shepherd), November 2007, now PDF at the
Meteorological Research Institute, The
Netherlands.
NGAI, J.H.Y., “Scanning Tunneling Spectroscopy
on Superconducting YBa2Cu3O7-ä ThinFilms: Effect of Ca-Doping, Quasiparticle Spin-
ZHAO, C.H., “Tropical and Extra-Tropical
Atmospheric Circulation Variability in the
Northern
Hemispheric
Troposphere”,
(G.W.K. Moore), June 2007, now PDF with
Natural Resources, Government of Canada.
UNIVERSITY OF VICTORIA
ANATOLIEVICH BOLOKHOV, Pavel, “Lorentz
Violation in Quantum Field Theory”,
(M. Pospelov), November 2007, now in the
Physics and Astronomy.
SANDERSON, Aaron, “Surface-Enhanced Raman
Scattering from a Modified Silver Elecctrode”,
(A.G. Brolo and J.M. Roney), June 2007, now
working with Dr. A.G. Brolo.
TIEU, Steven, “Structures of General Relativity”,
(F. Cooperstock), June 2007, present activities
unknown.
UNIVERSITY OF WATERLOO
ASHOORIOON, A., “Signatures of New Physics
from the Primordial Universe”, (Supervisor:
R. Mann), August 15, 2007, now a Post
Doctoral Fellow in the Physics Department of
the University of Michigan, Ann Arbor.
BOILEAU, J.C., “The Physical Underpinning of
Security
Proofs
for
Quantum
Key
Distribution”, (Supervisor: R. Laflamme),
September 21, 2007, now a Post Doctoral
Fellow at the University of Toronto Centre for
Quantum Information and Quantum Control.
3/11/2008
12:04 PM
Page 30
DEGREES AWARDED
DICK, M., “Spectroscopy of Selected Calcium and
Strontium Containing Polyatomic Molecules”,
(Supervisor: P. Bernath), May 13, 2007, now a
Post Doctoral Fellow at CalTech (California) in
the Jet Propulsion Lab.
CHAPMAN, G., "The Development of Ultrasonic
Techniques for Non destructive Evaluation of
Adhesive Bonds in Sheet Assemblies"
(R. Maev), May 2007 now Consultant with
Tessonics Corporation.
FAKHRAAI, Z., “Dynamics of Polymer Thin
Films and Surfaces”, (Supervisor: J. Forrest),
May 11, 2007, now a Post Doctoral Fellow in
the Department of Chemistry at the University
of Toronto.
CHERTOV, A., "Development of the New Physical
Method for Real Time Spot Weld Quality
Evaluation Using Ultrasound" (R. Maev),
August 2007 now Post Doctoral Fellow
University of Windsor.
KONOPKA, T., “Space and Particles at the Planck
Scale”, (Supervisors: F. Markopoulou &
R. Mann), June 2, 2007, now a Post Doctoral
Fellow at the Institute of Theoretical Physics in
the Netherlands.
SADLER, J., "A Ray Technique to Calculate the
Multiple Reflected and Transmitted Waves in
Layered Media" (R. Maev), September 2007,
now Post Doctoral Fellow University of
Windsor.
MOLAVIANJAXI, H., “New Route to Frustration
by Quantum Many-Body Effects in the Spin
Liquid Pyrochlore Tb2Ti2O7”, (Supervisor:
M. Gingras), May 7, 2007, now a Post Doctoral
Fellow in the Applied Mathematics Department
at the University of Waterloo.
UNIVERSITY OF WESTERN
ONTARIO
MYERS, C., “Investigating Photonic Quantum
Computation”, (Supervisor: R. Laflamme),
September 14, 2007, now a Post Doctoral
Fellow at the National Institute of Information
in Japan.
BARRIE, SCOTT B., “The Density Matrix
Method
in
Photonic
Bandgap
and
Antiferromagnetic Materials”, (M.R. Singh),
February 2007, now Instructor with Fanshawe
College, London, Canada.
THOMSON, R., “Holographic Studies of Thermal
Gauge Theories with Flavour”, (Supervisor:
R. Myers), August 8, 2007, now a Research
Associate in the Physics Department at
Carleton University.
MUKHERJI,
DEBASHISH,
“Molecular
Dynamics Studies of the Diffusion of Adsorbed
and Confined Polymer Film”, (M. Mueser),
October 2007, now PDF, Drexel University,
Philadelphia, Pennsylvania.
UNIVERSITY OF WINDSOR
CABRERA, R., "A Geometric Algebra Approach to
n-Qubit Systems" (W.E. Baylis), May 2007,
now Post Doctoral Fellow Princeton University.
30 C PHYSICS
IN
NGUYEN, MANH TRINH, “Spin-Save Excitations in Ferromagnetic Nanostructures”,
(M.G. Cottam), June 2007, now PDF position at
University of Western Ontario, subsequently
PDF position at Memorial University,
Newfoundland.
PENG, HAO, “Investigation of New Approaches to
Combined Positron Emission Tomography and
Magnetic Resonance Imaging Systems”,
(P.J. Simpson, B. Chronik), June 2007, now
PDF at Stanford University, Stanford,
California.
LINEHAN SHORLIN, KELLY A., “Thermodynamics and Kinetics of Clustering on
Surfaces”, (M. T. Zinke-Allmang), February
2007, now Laboratory Manager, Memorial
University, Newfoundland.
XU, SONGBO, “Immobilized Ferrocenium in
Tetraurea Calix[4]arene Heterodimers: Self
Assembly on Gold, Electrochemical Responses,
and Detection of Redox States by a Tip:
Towards Molecular Information Storage”,
(S. Mittler, M. T. Zinke-Allmang), October
2007, now PDF Ohio State University,
Columbus, Ohio.
YORK UNIVERSITY
BENEDEK, A., "Triple Differential Cross Section
Calculations For The Ionization of Molecular
Hydrogen and Helium by Positron Impact",
(R. Campeanu), October 2007, presently seeking employment.
PRADA, S., "Comprehensive Mass Spectometric
Analysis of Novel Organic Semiconductor
Molecules", (D. Bohme), October 2007, now a
Postdoctoral Fellow, Center for Biomaterials,
Faculty of Dentistry, University of Toronto,
Toronto, ON.
YAVIN, T., "Supersymmetry, Latice and Chromodynamic
Quantum
Field
Theories",
(R. Koniuk), June 2007, now a Postdoctoral
Fellow working for Dr. Kim Maltman,
Department of Mathematics and Statistics, York
University, Toronto, ON.
3/11/2008
12:04 PM
Page 31
BUREAU DE L’ACP
MARK YOUR CALENDARS:
JUNE 8 - 11, 2008
CAP CONGRESS, QUÉBEC CITY
An exciting program is in preparation for the 2008 annual Congress in Québec City, hosted by Laval University
on the occasion of the 400th anniversary of the founding of Québec. There will be much to celebrate at next
year's Congress, from the achievements of physicists in Canada and abroad, to the rich cultural heritage of beautiful Québec City.
The Congress will begin on Sunday, featuring a special session in Optics and Photonics dedicated to the memory of Dr. Roger Lessard, a Condensed Matter Physics Symposium: Magnetic Semiconductors towards Spinelectronics, and a number of topical parallel sessions organized by the specialized Subject Divisions of the CAP.
Sunday evening's Herzberg Memorial Public Lecture: Harnessing the Quantum World will be given by
Dr. Raymond Laflamme, a distinguished alumnus of Laval University, member of the Perimeter Institute,
Canada Research Chair, and Director of the Institute for Quantum Computing at the University of Waterloo.
The Congress will continue through Wednesday afternoon with a variety of invited and contributed sessions and
special events, selected highlights of which are outlined below.
In addition to the CAP's medal winners, plenary speakers will include Dr. Art McDonald of Queen's University,
Director of the Sudbury Neutrino Observatory and winner of numerous awards for the achievements of SNO,
and Dr. Eric Mazur of Harvard University, a leading researcher in both optical physics and physics education
who is renowned for developing the Peer Instruction method for interactive teaching.
The Congress will run in parallel with the High Performance Computing Symposium HPCS 2008, also held at
Laval University, and a special joint session: Numerical Physics is planned for Tuesday morning. In 2008, we
also celebrate the centenary of Rutherford's Nobel Prize, with his important connection to McGill University,
which will be featured in a special session arranged by the Division of the History of Physics, also on Tuesday,
and an exciting program is also planned for the High School Teacher's Workshop. The CAP's Best Student Paper
competition will be held on Wednesday morning, following a number of divisional student paper competitions
that will take place on Monday and Tuesday. The Congress banquet will be held on Tuesday evening at Laval
University. We look forward to seeing you there!
For updates and program information, bookmark the Congress web site at:
www.cap.ca/congress/congress.html
Abstract submission deadline: March 1, 2008
BUREAU DE L’ACP
A special public lecture on the history of science in Québec will be given on Monday evening by Jacques
Lacoursière, a renowned Québec historian, radio and television personality, and Member of the Order of
Canada. To encourage and facilitate participation in this special event, a light supper will be provided at the
poster session beginning late Monday afternoon.
The Congress will feature a special workshop on
Commercialization of Innovation on Monday afternoon, commencing with a plenary lecture by Mr. Haig Farris,
a leading venture capital entrepreneur specializing in hi-tech start-ups and resource industry technology companies, currently President of Fractal Capital Corp. in BC.
3/11/2008
1:12 PM
Page 32
CAP OFFICE
INSCRIVEZ À VOTRE AGENDA
LE CONGRÈS DE L'ACP DU 8 AU 10 JUIN
À QUÉBEC EN 2008!
Une programmation captivante est en préparation pour le Congrès de l'ACP à Québec en 2008 organisé par
l'Université Laval en ce 400ième anniversaire de la fondation de Québec. Les physiciens du Canada et de l'étranger unissent leurs réalisations à l'héritage historique de la ville de Québec en un florilège unique!
Le Congès débute le dimanche 8 juin par une session spéciale en Optique et photonique dédiée à la mémoire du
Prof. Roger A. Lessard, par un symposium sur la Physique de la matière condensée intitulé Semiconducteurs
magnétiques vers l'électronique de spin et par des sessions parallèles sous l'égide de Divisions de l'ACP. La conférence publique à la mémoire de Herzberg du dimanche soir, Domestication du monde quantique, sera donnée
par le Dr Raymond Laflamme, un diplômé de renom de l'Université Laval et membre du Perimeter Institute,
détenteur d'une chaire du Canada et directeur de l'Institut en calculs quantiques de l'Université de Waterloo. Le
Congrès se poursuit jusqu'au mercredi après-midi avec diverses sessions de présentations invitées, de communications et d'événements spéciaux détaillés plus bas.
Une conférence publique spéciale sera donnée le lundi soir par Jacques Lacoursière, un historien québécois
membre de l'Ordre du Canada connu par sa présence dans les médias et par les nombreux prix qu'il a reçus. Pour
permettre la participation à cette soirée spéciale, un repas léger sera offert en fin d'après-midi lors de la session
pour affiches. La programmation du lundi après-midi inclut un atelier spécial sur la Commercialisation des innovations qui va débuter par une présentation invitée de M. Haig Farris, un entrepreneur de renom qui se spécialise
dans le démarrage de compagnies en haute technologie. Il est présentement président de la compagnie Fractal
Capital Corp. de la Colombie britannique.
CAP OFFICE
En plus des gagnants des médailles de l'ACP, les sessions plénières vont inclure le Dr Art McDonald de
l'Université Queen's, directeur de l'observatoire de neutrinos de Sudbury (SNO) et gagnant de nombreux prix
pour les réalisations de ce laboratoire, et du Dr Eric Mazur de l'Université Harvard, un leader en recherche dans
le domaine de l'optique et de l'éducation en physique qui est aussi renommé pour le développement de la méthode Peer Instruction en enseignement interactif
Le Congrès se déroulera en même temps que le Symposium sur les calculs de haute performance HPCS 2008
qui se tiendra aussi à l'Université Laval. Une session spéciale conjointe en Physique numérique aura lieu le
mardi après-midi. En 2008, nous célébrons aussi le centenaire du prix Nobel de Rutherford qui séjourna à
l'Université McGill; cette commémoration se fera dans une session organisée par la Division de l'histoire de la
physique, aussi le mardi, et par le captivant programme de l'Atelier des professeurs du collégial. La compétition
de la meilleure présentation étudiante se tiendra le mercredi avant-midi, à la suite des diverses compétitions qui
auront lieu dans les divisions le lundi et le mardi. Le banquet aura lieu le mardi sur le campus. Nous seront
heureux de vous recevoir à Québec!
Pour les dernières nouvelles et l'information sur le programme, consultez le site internet du Congrès à
l'adresse suivante :
32 C PHYSICS
www.cap.ca/congress/congress-f.html
La date limite de soumission des résumés est le 1er mars 2008
IN
3/11/2008
12:04 PM
Page 33
BUREAU DE L’ACP
2008 HERZBERG MEMORIAL PUBLIC LECTURE
CONFÉRENCE COMMÉMORATIVE PUBLIQUE HERZBERG 2008
Université Laval University
Sunday/Dimanche, 8 June/juin 2008
19h00
Harnessing the Quantum World
Maîtriser le monde quantique
Raymond Laflamme, IQC/U.Waterloo
Information processing devices are pervasive in our society; from the 5 dollar watches to a
multi-billion dollar satellite network. These devices have allowed the information revolution which is developing around us. It has transformed not only the way we communicate
or entertain ourselves but also the way we do science and even the way we think. All this
information is manipulated using the classical approximation to the laws of physics, but we
know that there is a better approximation: the quantum mechanical laws. Would using quantum mechanics for information processing be an impediment or could it be an advantage?
This is the fundamental question at the heart of quantum information processing (QIP). QIP
is a young field with an incredible potential impact reaching from the way we understand
fundamental physics to technological applications. I will give an introduction to quantum
information by stressing recent interesting developments. I will also comment on the effort
in this field at Waterloo and in Canada.
Les dispositifs de traitement d'information se retrouvent partout dans notre société, des montres à 5 dollars aux réseaux de satellites qui en valent des milliards. Ils ont permis la révolution informatique qui se développe autour de nous. Cette révolution a transformé notre
façon de communiquer et de nous distraire, mais aussi notre manière de faire la science et
même de penser. Toute cette information est manipulée en utilisant l'approximation classique des lois de la physique. Pourtant, nous savons qu'il y a une meilleure approximation:
celle des lois quantiques. L'utilisation de la mécanique quantique pour le traitement de l'information est-elle un frein, ou peut-elle être un avantage? Voilà la question fondamentale
au coeur du traitement quantique de l'information (TQI). Le TQI est un domaine jeune avec
un impact potentiel incroyable allant de la façon de comprendre la physique fondamentale
aux applications technologiques. Je vais présenter une introduction à l'informatique quantique en insistant sur de récents développements intéressants. Je vais également faire un survol des travaux dans ce domaine effectués à Waterloo et au Canada.
3/11/2008
12:04 PM
Page 34
CAP OFFICE
INVITED SPEAKERS /
CONFÉRENCIERS INVITÉS
CLINE, James ( DTP / DPT )
McGill University
Nongaussianity in the Cosmic Microwave Background from Nonlocal
Inflation Models
COUCHMAN, Hugh ( CAP / ACP )
McMaster University
Computational Astrophysics
AGUILO, Ernest ( PPD / PPD )
University of Alberta and York University
Latest Results of the DZero Experiment
ALBERT, Jacques ( DOP / DOP )
Carleton University
Multiparameter sensing mechanisms from gratings in optical fibers
DAMASCELLI, Andrea ( DCMMP-DIMP / DPMCM-DPIM )
The Legacy of Einstein's Photoelectric Effect: From Light Quanta to
Quantum Phenomena in Solids
BACCA, Sonia ( DNP-DTP / DPN-DPT )
TRIUMF
Ab Initio Reactions of Light Nuclei
DAVOUR, Anna ( PPD / PPD )
Queen's University
The PICASSO Dark Matter Search Project
BARRETTE, Jean ( DHP / DHP )
McGill University
Ernest Rutherford at McGill
DESGRENIERS, Serge ( DCMMP-DIMP / DPMCM-DPIM )
Université d'Ottawa
X-ray Micro-Diffraction: A Remarkable Tool for the Study of Condensed
Matter Under Extreme Conditions
BEACH, Kevin ( DCMMP / DPMCM )
Simulating frustrated spin systems using valence bonds
BEHR, John ( DNP / DPN )
TRIUMF
Standard Model tests by measurement of the daughter nucleus momentum
from laser-trapped radioactives
BERCIU, Mona ( DCMMP / DPMCM )
Manipulating spin and charge in diluted magnetic semiconductors
BERTRAM, Allan ( DSS / DSS )
Heterogeneous atmospheric chemistry at night
BEYEA, Steven ( DMBP / DPMB )
National Research Council of Canada
Novel Acquisition Techniques for High Field Functional MRI (fMRI)
BLANCHARD, Vincent ( DPP / DPP )
Ecole Polytechnique de Montréal
Plasma technology for the wood product industry
BOUDOUX, Caroline ( DOP-DMBP / DOP-DPMB )
to be announced / à venir
BOULAY, Mark ( PPD / PPD )
Queen`s University
Status of DEAP/CLEAN at SNOLAB
CADOGAN, Sean ( DCMMP / DPMCM )
Magnetism, Valence and the Magnetocaloric Effect in R5(Si,G3)4 compounds
(rare-earth)
PLENARY
CHAPMAN, Dean ( DIAP-DIMP / DPIA-DPIM )
University of Saskatchewan
The Biomedical Imaging and Therapy Beamline at the Canadian Light Source
CHAPMAN, Gilbert ( DIAP / DPIA )
Daimler Chrysler / NSERC Industrial Research Chair, University of Windsor
The Greening of Ground Transportation in North America
CHBIHI, Abdelouahad ( DNP / DPN )
GANIL
Exploring the symmetry energy with isospin effects in heavy-ion collisions
CHEN, Qiying ( DOP-DMBP / DOP-DPMB )
Memorial University of Newfoundland
Fibre Bragg gratings for optical biosensors
34 C PHYSICS
IN
DUAN, Luming ( DAMPhi-DOP / DPAMip-DOP )
University of Michigan, Ann Arbor
Controlling interaction of ultracold atoms in an optical superlattice
ELFIMOV, Ilya ( DCMMP / DPMCM )
Novel aspects in oxide's physics
FARRIS, Haig ( CAP / ACP )
PLENARY
Fractal Capital Corp.
Understanding the Venture Capital World
FLEMING, George ( DTP / DPT )
Yale University
Lattice Study of the Conformal Window in QCD-like Theories
FRASER, James M. ( DOP / DOP )
Queen`s University
Ultrafast Dynamics of a Single-Walled Carbon Nanotube
FRISKEN, Barbara ( DCMMP / DPMCM )
Carbopol - Microrheology and Microstructure
FROHLICH, Carla ( DNP / DPN )
University of Chicago
Nuclear Physics Aspects of an Astrophysical Nucleosynthesis Process
BRANDENBERGER, Robert ( DTP / DPT )
McGill University
Progress in String Gas Cosmology
CAMPBELL, John ( CAP / ACP )
University Canterbury New Zealand
Rutherford - His Path to the Nobel Prize
DIXIT, Mandu ( PPD / PPD )
Carleton University
The International Linear Collider - a precision probe for physics in the postLHC era
GARCIA-SUCERQUIA, Jorge ( CAP-DOP / ACP-DOP )
COPL, Université Laval
Digital Holography: A Modern Perspective of Denis Gabor’s Invention
GILBERT, Raymond ( DIAP / DPIA )
Opsun Technologies Inc.
Solar Energy Extraction: A Real Challenge for Physicists / L’Extraction de
l'énergie solaire, un défi de taille pour les physiciens
GRAHAM, Kevin ( PPD / PPD )
Carleton University
Measuring Neutrino Mass with EXO
GRIFFIN, Allan ( DHP / DHP )
100 years of Liquid Helium: Highlights of Canadian Research
GWINNER, Gerald ( DNP / DPN )
Test of relativistic time dilation with fast optical atomic clocks at different
velocities
HALL, Kimberley ( DOP / DOP )
Ultrafast Control of Spin Dynamics
HARRISON, David (DPE / DEP)
Implementing Physics Practicals
3/11/2008
12:04 PM
Page 35
BUREAU DE L’ACP
HAWKES, Robert ( DPE / DEP )
Mount Allison University
Guided Collaborative Learning: Not Just for First Year Physics
HEGMANN, Frank (DPP / DPP )
High intensity THz pulse generation and imaging at ALLS
LOCKYER, Nigel ( PPD-DNP / PPD-DPN )
TRIUMF
TRIUMF: Developing Plans for an Experimental Program in Fundamental
Symmetries with Actinide Targets
LOGAN, Heather ( DTP-PPD / DPT-PPD )
Carleton University
What's new at the energy frontier
HILL, Ian ( DCMMP / DPMCM )
The Importance of Interfaces in Organic Electronic Devices
HOLT, Richard ( DAMPhi / DPAMip )
Recent progress in fast-ion-beam laser measurements of atomic data for astrophysics
HOLVOET, Servaas ( DPP / DPP )
Laval University
Nano-coatings and Surface Functionalisation : Towards High-Performance
Vascular Biomaterials
HUBER, Garth ( DNP / DPN )
Physics Potential of the Jefferson Lab 12 GeV Upgrade
HU, Can-Ming ( DCMMP / DPMCM )
Spin Dynamics in Ferromagnetic and Spintronic Materials
LVOVSKY, Alexander ( DAMPhi-DOP / DPAMip-DOP )
Quantum memory for continuous-variable optical states
MAEVA, Elena ( DIAP / DPIA )
University of Windsor
New BioCar Ontario Initiative: Biocomposite materials
MALONEY, Alexander ( DTP / DPT )
McGill University
Partition Functions of Three Dimensional Quantum Gravity
MANDELIS, Andreas ( DMBP-DIMP / DPMB-DPIM )
Centre for Advanced Diffusion Wave Technologies : Quantum Dental
Technologies
Investigation of Demineralization and Remineralization of Human Teeth using
Infrared Photothermal Radiometry and Modulated Luminescence
MANN, Robert ( DTP / DPT )
Boundaries Unbound
JANISSEN, Lee Ann ( CAP / ACP )
TD Securities
A Physicist’s Career in the Wholesale Banking World
MARGOT, Joelle ( DPP / DPP )
Plasma-Québec : a unique strategic network in Plasma Science and
Applications
JANSSENS, Robert ( DNP / DPN )
Argonne National Laboratory
Hunt for new shell structure in neutron-rich nuclei
JIRASEK, Andrew ( DMBP / DPMB )
University of Victoria
Polymer gel dosimetry for 3D dose verification in radiation therapy
KANUNGO, Rituparna ( DNP / DPN )
Saint Mary's University
Nuclear halos : A new era in nuclear physics
MARSIGLIO, Frank ( DMBP / DPMB )
Flippin' Spins: a Quantum Mechanical Approach
MARTIN, John ( PPD / PPD )
The History and Physics Impact of the HERA e-p Collider
MARTINU, Ludvik ( DPP / DPP )
École polytechnique
Low pressure plasma processing / Plasma-surface interactions
KAVANAGH, Karen ( DCMMP / DPMCM )
Magnetic Semiconductors - The Basics
MAZUR, Eric ( CAP / ACP )
PLENARY
Harvard University
Confessions of a converted lecturer
KIEFFER, Jean-Claude ( DPP / DPP )
Université du Québec, INRS
MAZUR, Eric ( DPE / DEP )
Harvard University
KILFOIL, Maria ( DMBP / DPMB )
McGill University
MCDONALD, Art ( CAP / ACP ) PLENARY
Queen`s University
SNO and the New SNOLAB Underground Facility
KRUSHELNICK, Karl ( PPD / PPD )
University of Michigan
Compast laser-plasma based accelerators
MCKELLAR, A. Robert ( DAMPhi-DIMP / DPAMip-DPIM )
National Research Council
Longer wavelengths, higher resolution, and greater absorption paths with the
far infrared beamline at the Canadian Light Source
LACOURSIÈRE, Jacques ( CAP / ACP )
Petite histoire des sciences et de leur enseignement au Québec
LAFLAMME, Raymond ( CAP / ACP )
PLENARY
Institute for Quantum Computing / University of Waterloo
Harnessing the Quantum World / Maîtriser le monde quantique
LANGILL, Philip P. ( DPE / DEP )
MELKO, Roger ( DCMMP / DPMCM )
Quantum Phase Transitions via Large-Scale Computing
METLITSKI, Max ( DTP-PPD / DPT-PPD )
Harvard University
Duality and Wilson Loops in Non-Compact U(1) Gauge Theories
LEBEL, Céline ( DTP-PPD / DPT-PPD )
The ATLAS detector at LHC
MEUNIER, Michel ( DIAP-DIMP / DPIA-DPIM )
Ultrafast laser processing of nanomaterials for biomedical applications
LEONELLI, Richard ( DCMMP / DPMCM )
Ga(In)AsN: an unusual semiconductor alloy
LEWIS, Laurent ( DTP-DCMMP / DPT-DPMCM )
Laser ablation with short and ultrashort laser pulses: basic mechanisms from
MD simulations
MILNER-BOLOTIN, Marina ( DPE / DEP )
Ryerson University
Physics for Architects: Design, Implementation and Evaluation of Innovative
Physics Curricula
MOUSSEAU, Normand ( CAP / ACP )
Simuler la dynamique des protéines
3/11/2008
12:04 PM
Page 36
CAP OFFICE
PAGE, John ( DCMMP / DPMCM )
Localization of ultrasound in a three-dimensional elastic network
ROTTLER, Joerg ( DMBP / DPMB )
Deformation, flow and aging in glassy materials
PATITSAS, Steve S.N. ( DCMMP / DPMCM )
STM studies of the dissociation of trichloroethylene on silicon surfaces:
Possible consequences for thin film growth
ROY, Jean-Ives ( CAP / ACP )
INO
How INO brings innovation to help companies improve their competitive edge
and contributes to their development.
PEAK, Derek ( DSS / DSS )
Mineral structure, surface complexation, and the solid/water interface :
Insights on general aqueous surface chemistry fromm ATR-FTIR and XAS studies of S and Se oxyanion adsorption
RUPRECHT, Gotz ( DNP / DPN )
TRIUMF
TACTIC - a tracking detector for ions from nuclear reactions
PELLING, Andrew ( DMBP / DPMB )
University College London
Mechanics in the Moment
PETRY, Robert ( DNP / DPN )
Lattice methods for light-quark mesons
PICHÉ, Michel ( DAMPhi-DOP / DPAMip-DOP )
Université Laval
Acceleration of charged particles using ultrafast transverse magnetic laser
beams of multiterawatt power
PICKET, Warren ( DCMMP / DPMCM )
University of California Davis
Correlated Electrons I: Applications from DFT through DMFT to Complex
Materials
POEPPING, Tamie ( DMBP / DPMB )
Vascular Modeling and Hemodynamics Research Using Ultrasound and
Particle Imaging
POISSON, Eric ( DTP / DPT )
Black holes in tidal environments
POND, James ( DIAP / DPIA )
Lumerical Solutions Inc.
Rigorous electromagnetic simulation of current and next-generation photonic
devices: challenges and opportunities
PREDOI-CROSS, Adriana ( DAMPhi / DPAMip )
Laboratory spectroscopy for planetary remote sensing
PYWELL, Rob ( DHP / DHP )
A Scrapbook History of Physics at the University of Saskatchewan
RAGAN, Ken ( PPD / PPD )
McGill University
Results of the first year of operation of the VERITAS ground-based gamma-ray
observatory
RAHILLY, Tony ( CAP / ACP )
NRC - IRAP
From Physics in the Lab to Products at the Retailer: The Speed of Innovation
and the Acceleration of Commercialization
ROBERTSON, Steven ( PPD / PPD )
Institute for Particle Physics / McGill University
Recent results from the BABAR experiment
ROBINSON, Joseph ( DPP / DPP )
Imperial College, UK
ROOT, John ( DHP / DHP )
National Research Council Canada
The National Research Universal (NRU) Reactor – Fifty years of Excellence
ROSS, Amanda ( DAMPhi / DPAMip )
Université Lyon
Laboratory exploration of gas phase spectra of some transition metal hydrides.
ROSS, Stephen ( DAMPhi / DPAMip )
University of New Brunswick
Selected Aspects of Large Amplitude Motion in Molecules
36 C PHYSICS
IN
SARKAR, Dilip ( DPP / DPP )
DSA, University of Quebec
Superhydrophobic and icephobic coating by plasma process
SHEN, Jun ( DIMP / DPIM )
National Research Council Canada
Top-hat cw laser induced time-resolved mode-mismatched thermal mirror and
thermal lens spectroscopies
SKOROBOGATIY, Maksim ( DOP / DOP )
Ecole Poly Montreal
Photonic textiles and their applications
STAFFORD, Luc ( DPP / DPP )
Studies of plasma reactions on dynamic surfaces using a novel rotating substrate technique
SULLIVAN, Donald Edward ( DTP-PPD / DPT-PPD )
Field Theory for Polymeric Materials
SUNIL KUMAR, P.B. ( DMBP / DPMB )
Indian Institute Tech. Madras
Strain hardening, avalanches and strain softening in dense cross-linked actin
networks
TELENKOV, Sergey ( DMBP-DIMP / DPMB-DPIM )
To be announced / à venir
TREMBLAY, André-Marie ( CAP / ACP )
Université de Sherbrooke
Insights into high-temperature superconductors from high-performance computing
TREMBLAY, Pierre ( DAMPhi-DIMP / DPAMip-DPIM )
Université Laval
To be announced / à venir
TROTTIER, Howard ( CAP / ACP )
Quantum Chromodynamics on a Space-time Lattice
VENUS, David ( DCMMP / DPMCM )
McMaster University
Measurements of static and dynamic susceptibility exponents of an ultrathin
ferromagnetic film
VETTERLI, Mike ( CAP / ACP )
Simon Fraser University/TRIUMF
ATLAS Computing : Dealing with PetaBytes of Data per Year
VIDAL, François ( DPP / DPP )
Institut national de la recherche scientifique
Laser ablation threshold dependence on pulse duration and wavelength for
corneal tissues: experiments and modeling
WARBURTON, Andreas ( PPD / PPD )
McGill University
Recent Results from the Collider Detector at Fermilab (CDF)
WRIGHT, Alex ( PPD / PPD )
Queen's University
The SNO+ Experiment at SNOLAB
XU, Yuan ( DMBP-DIMP / DPMB-DPIM )
Ryerson University
Magneto-Acousto-Electrical Tomography: a Potential Imaging Modality for
Electrical Impedance
3/11/2008
12:04 PM
Page 37
LIVRES
BOOKS RECEIVED / LIVRES REÇUS
The following books have been received for review. Readers are
invited to write reviews, in English or French, of books of interest to
them. Books may be requested from the book review editor,
Richard Hodgson by using the online request form at
http://www.cap.ca.
Les livres suivants nous sont parvenus aux fins de critique. Celles-ci
peuvent être faites en anglais ou en français. Si vous êtes intéressé(e)s
à nous communiquer une revue critique sur un ouvrage en particulier, veuillez vous mettre en rapport avec le responsable de la critique
des livres, Richard Hodgson par internet à http://www.cap.ca.
A list of ALL books available for review, books out for review, and
copies of book reviews published since 2000 are available on-line -see the PiC Online section of the CAP's website :
http://www.cap.ca.
Il est possible de trouver électroniquement une liste de livres
disponibles pour la revue critique, une liste de livres en voie de révision, ainsi que des exemplaires de critiques de livres publiés depuis
l'an 2000, en consultant la rubrique "PiC Électronique" de la page Web
de l'ACP : www.cap.ca.
GENERAL INTEREST
PHYSICS & ENGINEERING OF RADIATION DETECTION, Syed Naeem
Price: $70/$96.
Ahmed, Elsevier Publishers, 2007; pp. 764; ISBN: 978-0-12-045581-2
(hc); Price: $95.00 US.
UNSTOPPABLE GLOBAL WARMING: EVERY 1,500 YEARS, S. Fred
QUANTUM GRAVITY, Carlo Rovelli, Cambridge University Press,
Singer and Dennis T. Avery, Rowman & Littlefield Publishers Inc.,
2008; pp. 278; ISBN: 978-0-7425-5124-4 (pbk); Price: $19.95.
2007; pp. 451; ISBN: 978-0-521-71596-6 (pbk); 978-0-521-83733-0 (hc);
GRADUATE TEXTS AND PROCEEDINGS
DRIVING FORCES IN PHYSICAL, BIOLOGICAL AND SOCIO-ECONOMIC
PHENOMENA, Bertrand M. Roehner, Cambridge University Press,
Shiryayev, D.L. Pagan, Cambridge University Press, 2007; pp. 359;
ISBN: 978-0-521-85121-3 (hc); Price: $135.00.
2007; pp. 254; ISBN: 978-0-521-85910-3 (hc); Price: $75.00.
PROTEIN CONDENSATION - KINETIC PATHWAYS TO
CRYSTALLIZATION AND DISEASE, James D. Gunton, Andrey
ZERO TO INFINITY: THE FOUNDATIONS OF PHYSICS, Peter Rowlands,
World Scientific Publishing Co., 2007; pp. 713; ISBN: 978-9812709141-6544 (hc); Price: $88.00.
BOOK REVIEWS / CRITIQUES DE LIVRES
Book reviews for the following books have been received and posted to the Physics in Canada section of the CAP’s website :
http://www.cap.ca. Review summaries submitted by the reviewer are included; otherwise, the full review can be seen at the url listed with
the book details. [NOTE: Short reviews received for books listed in the January to September 2007 issues are included as well.]
Des revues critiques ont été reçues pour les livres suivants et ont été affichées dans la section “La Physique au Canada” de la page web de
l’ACP : http://www.cap.ca. Les versions abrégées des critiques ont été incluses quand disponibles. Les versions complètes sont sur le
web. [N.B. Ont aussi été incluses les versions abrégées des critiques annoncées dans les numéros de janvier à octobre 2007.]
A MODERN APPROACH TO CRITICAL
PHENOMENA, Igor Herbut, Cambridge
Bechhoefer, Simon Fraser University; posted
2/11/2008; To read the detailed review, please see
http://www.cap.ca/brms/reviews/Rev836_602.pdf ]
analysis in which the estimation of uncertainties
in measured quantities plays an important role.
At first thought, such a subject seems "classical"
and unchanging, but, in fact, four recent developments have transformed the subject: the growing
power and ease of use of data acquisition devices
and computer and analysis software; the triumph
of Bayesianism as a theoretical underpinning of
data analysis that provides clearer motivations
for different procedures; the growth of fields of
physics such as single-molecule biophysics that
depend more heavily on statistics than traditional
areas; and the improvements in manufacturing
techniques that have increased the need for standardization in terminology and techniques for
data analysis and the estimation of uncertainties.
For the past few years, I have taught a secondyear laboratory course on data acquisition and
It is this last development that seems to have
motivated the new book by Les Kirkup and Bob
University Press, 2007; pp. 207; ISBN: 978-52185452-8 (hc); Price: $65.00. [Review by Lara
Thompson, UBC; posted 2/11/2008; To read the
detailed review, please see http://www.cap.ca/brms/
reviews/Rev864_597.pdf ]
AN INTRODUCTION TO UNCERTAINTY IN
MEASUREMENT, L. Kirkup, R.B. Frenkel,
Cambridge University Press, 2006; pp. 233;
ISBN: 0-521-84428-2 (hc); 0-521-60579-2
(pbk); Price: $80/$34.49. [Review by John
Frenkel, An Introduction to Uncertainty and
Measurement using the GUM (Guide to the
Expression of Uncertainty in Measurement)
(Cambridge Univ. Press, 2006). Kirkup and
Frenkel's book is aimed at first- and second-year
university laboratory courses. As its title suggests, it introduces the GUM, an internationally
supported effort to standardize definitions and
concepts having to do with accuracy, error, precision, and uncertainty in measurement. As discussed in the detailed review, the new perspective has some interesting aspects that instructors
may wish to note. In addition, there are some
nice examples and specific discussions that are
similarly useful. However, the book is overall a
rather old-fashioned one and fails to take into
account in a serious way the major advances discussed above. In the end, I do not see a reason
for switching from the text we currently use,
3/11/2008
12:04 PM
Page 38
BOOKS
which, although old fashioned in its own way, is
better pedagogically.
John Bechhoefer
Burnaby, British Columbia, Canada
AN INTRODUCTION TO COMPUTATIONAL
PHYSICS, SECOND EDITION, Tao Pang,
Cambridge University Press, 2006, pp: xvi + 368,
ISBN 0521825695 (hc); Price: US$70.00
[Review by David P. Maroun, BC; posted
2/22/2007; to read the detailed review, please see
http://www.cap.ca/brms/reviews/Rev819_534.pdf ]
This is a book of mathematical techniques for
solving a great variety of physical problems. The
book uses the Java computer programming language. Programs in C++ and FORTRAN are
available on the author's Web sites. Parts of the
book are purely analytic, and do not use computer programs. I recommend the book to those who
are already capable of computer programming,
can interpret programs that have little documentation, and are familiar with the physics and
mathematics involved.
David Maroun
B.C.
INTEGRAL CONSCIOUSNESS AND THE
FUTURE OF EVOLUTION, S. McIntosh, Paragon
House 2007, pp: 371, ISBN 978-1-55778-867-2;
Price: $25.00 hc [review by Colin Carbno, SaskTel;
posted 2/03/2008; to read the detailed review, see
http://www.cap.ca/brms/reviews/Rev899_616.pdf]
QUANTUM THEORY OF THE ELECTRON
LIQUID, Gabriele F. Giuliani and Giovanni
Vignale, Cambridge University Press, 2005; pp.
777; ISBN: 0-521-82112-6 (hc); Price: 90.00.
[Review by Tapash Chakraborty, Winnipeg,
Manitoba; posted 2/11/2008; To read the detailed
review, please see http://www.cap.ca/brms/reviews/
Rev756_541.pdf ]
RHÉOPHYSIQUE, Patrick Oswald, Éditions
Belin, 2005; pp. 603; ISBN: 2-7011-3969-4
(pbk); Price: 40 (GB). [Review by Béla Joós,
coeur de pouvoir de temps à autre lire un ouvrage
en français, surtout un qui est bien écrit. En plus
de l’éducation scientifique, j’ai découvert toute
une terminologie dont je ne connaissais que
l’équivalent anglais. Cet ouvrage s’adresse aux
étudiants du deuxième ou troisième cycle avec
une bonne base mathématique. Il rassemble des
sujets que d’habitude on ne retrouverait pas dans
le même volume, en particulier parce qu’ils ne
sont pas en général du domaine d’expertise de
scientifiques qui travaillent ensemble. A mesure
que les barrières entre classes de matériaux
s’estompent, ou plus précisément les classes de
matériaux s’étendent jusqu’à former des ensembles quasi continus d’une classe à l’autre, on peut
s’attendre à ce qu’un traitement unifié de l’effet
des déformations va se développer. L’unité se
reflète dans le traitement mathématique et l’emphase sur les propriétés du milieu comme un continuum : à une limite il y a les solides cristallins
à l’autre les liquides isotropes.
Après une introduction générale, et des généralités sur les matériaux et leurs comportements
rhéologiques, suivent des chapitres sur la
mécanique des milieux continus, l’hydrodynamique des liquides simples, et l’élasticité des
solides. Ces formalismes sont ensuite utilisés
pour développer les modèles familiers utilisés
pour l’étude de la plasticité et la rupture des
solides, et la viscoélasticité des matériaux
isotropes. Suivent des applications plus spécifiques sur les polymères fondus, vulcanisés, en
solution, les micelles, et un long chapitre sur les
cristaux liquides. La valeur du livre est surtout
dans son exposition claire des modèles mathématiques. Le livre à ce chapitre est presque encyclopédique, et est une source précieuse d’inspiration et de point de départ pour les travaux sur des
matériaux plus complexes.
Pour les anglophones une version anglaise, me
dit-on, est en préparation et sera publiée par
Cambridge University Press.
B. Joós
Université d’Ottawa
Ottawa, Ontario; posted 6/18/2007; To read the
reviews/Rev802_488.pdf]
SPECTROGRAPH DESIGN FUNDAMENTALS,
John James, Cambridge University Press, 2007;
pp. 191; ISBN: 978-0-521-86463-3 (hc); Price:
$120.00. [Review by Scott Teare, Professor and
Dans un monde scientifique dominé par les
manuels en langue anglaise, cela réchauffe le
Department Chair; posted 2/11/2008; To read the
reviews/Rev870_599.pdf ]
38 C PHYSICS
IN
“Spectrograph Design Fundamentals” is an
excellent choice for scientists and engineers who
are looking to understand more about an instrument they have or may want to build in support
of spectrally analyzing light.
This book takes on the challenge of providing
critical information on the important considerations in designing and building several types of
spectrographs. Chapters include coverage of the
fundamental topics: geometric and physical
optics; aberration theory; detectors; optical and
mechanical design; alignment and calibration. In
addition there are separate chapters on the specific types of spectrographs ranging from prism and
grating spectrographs to concave grating and
interference spectrographs.
Those who are more advanced in their understanding of spectrometers will also find the book
useful for their libraries as the author does a very
good job of connecting fundamental concepts
throughout the book and these to specific spectrometer types. A valuable feature of this book is
that equations supporting the various spectrograph types, their performance, advantages, and
applications are supported by well written text,
often supported by clear diagrams making the
material very accessible.
All in all, the book is extremely readable and provides an excellent foundation for scientists and
engineers who are considering building a spectrograph or want a deeper understanding of the
fundamentals of an instrument already in the laboratory. The references in the book do appear a
little dated and there are fewer than one might
like, however, this should not detract from the
applicability and usability of the book for many
readers.
Scott W. Teare, P.Phys.
Chairman and Professor of
Engineering, New Mexico Tech
Socorro, New Mexico USA
Electrical
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Physics in Canada La Physique au Canada

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