CANADIAN ASSOCIATION OF PHYSICISTS

ASSOCIATION CANADIENNE DES PHYSICIENS ET PHYSICIENNES

The Canadian Association of Physicists (CAP) is pleased to announce that the 2004 CAP Medal for Lifetime Achievement in Physics is awarded to Dr. Michael Thewalt, Simon Fraser University, for his advances in the study of silicon and semiconductors and for his breadth as an experimentalist.

Following his bachelors degree from McMaster in 1972, Mike Thewalt alternated between the east and west coasts, with graduate work at UBC and postdoctoral studies at IBM in Yorktown Heights, before finally settling on a west coast locale at Simon Fraser University in 1980. His observations of bound multi-exciton complexes in silicon brought him international attention, and he was awarded a Sloan Fellowship in 1982. His early fascination with the optical properties of silicon has developed into a broad program of semiconductor research, which even included an important application in the rather unrelated field of archeometry.

Silicon is one of the most important industrial materials of the modern day, and judging by Michael's most recent work, its intriguing optical properties are far from being fully catalogued or understood. Michael's research concentrates on the energy spectra and lifetimes of excitons, the electron-hole analogues of the electron-proton bound state that is the hydrogen atom. Pivotal to the development and testing of the theoretical description of excitons, his work includes definitive studies of bound multi-exciton complexes, biexcitons, and, in 1987, the first observation of polyexcitons, whose existence had been predicted by Kittel a decade and a half earlier. Polyexcitons are the solid state representation of a collective state of individual excitons. Over the last 15 years, these fundamental studies expanded into a broad assault on the properties of semiconductors, including many systems of considerable technological importance, such as strained SiGe/Si heterostructures, and most recently, GaAsSb/InP heterostructures.

The measurement of exciton linewidths in high-quality samples often requires much higher precision than is available from conventional instruments, and one of Thewalt's many strengths has been the continued introduction of new instrumentation to make these measurements possible. He deserves credit for the development of such tongue-twisting techniques as Fourier-transform far-infra photoinduced absorption spectroscopy and near-infrared high-resolution Fourier-transform photoluminescence spectroscopy. Michael's breadth as an experimentalist is evidenced by his interdisciplinary collaborations, which have ranged from archeometry to the study of photosynthesis. For example, the method that he co-developed for the optical dating of sediments is finding widespread application in archeology and is his most heavily cited paper.

Outside of the lab, Mike Thewalt's contributions to the Canadian physics community have included substantial committee responsibilities with NSERC, IUPAP, and the executive of CAP, including its presidency. He was founding member of the Pacific Centre for Advanced Materials and Microstructure in Vancouver, and committed many stressful and sometimes frustrating hours to the NSERC reallocation process. Recognition of his work can be seen in the awards that he has received, such as the Rutherford Medal of the Royal Society of Canada (1994) and the Gold Medal of the BC Science Council (1987). Not unexpectedly, Michael has been made a fellow of the American Physical Society, the Royal Society of Canada, and the Institute of Physics. For 2004, he is one of nine recipients nationally of a fellowship from the Killam Foundation.

The CAP Medal for Lifetime Achievement in Physics was introduced in 1956 and is awarded annually. Dr. Thewalt will receive the 2004 Prize during the CAP's awards banquet to be held at the Delta Hotel in Winnipeg on June 15th, 2004.

The Canadian Association of Physicists, founded in 1945, is a professional association representing over 1600 individual physicists and physics students in Canada, the U.S. and overseas, as well as a number of Corporate and Departmental Members. In addition to its learned activities, the CAP also undertakes a number of activities intended to encourage students to pursue a career in physics.

For more information, please contact:

Canadian Association of Physicists
Tel: (613) 562-5614
Fax: (613) 562-5615
E-mail: cap@physics.uottawa.ca