Presented by: Jacques Vanier (Département de physique, Université de Montréal).
The lecture will cover one of the most fascinating subject, that of atomic frequency standards used to measure time with great accuracy. Of all measurements of physical quantities, time, a quantity that we have difficulty to define and interpret physically, is the quantity that we can measure most accurately. This is due to the practical realization of clocks that use atomic properties. These so-called atomic clocks have made possible the verification of the validity of basic physics theories such as that of relativity. They also have made possible implementation of systems, such as the Global Positioning System, know as GPS. Such a system, using atomic clocks in Earth satellites, has made possible accurate physical positioning everywhere on the surface of the planet, an easy operation available to anyone. These standards are also the most precise instruments ever realized in research laboratories and in National Institutes responsible of standards representing the International System of Units (SI). I will describe the physics of operation of these instruments, particularly new developments using optical techniques, such as laser cooling, permitting the realization of precision of the order of parts in 1018. I will include in the presentation a short description of the most important applications of these clocks.
About the speaker
Jacques Vanier completed his undergraduate studies in physics at the University of Montreal before moving to McGill University to undertake his graduate studies. During his career, he has worked in industry (Varian, Hewlett-Packard), taught physics and established a research laboratory in quantum electronics at Laval University, Québec, Canada. He has worked at the National Research Council of Canada in Ottawa, where he founded the Institute for National Measurement Standards and was his director until 1994. His research work was oriented towards the understanding and the application of quantum electronics phenomena and he has been a consultant for several companies engaged in the development of atomic clocks. Vanier has also been very active on the academic circuit, giving lectures and making presentations at numerous conferences in Universities, National Institutes and Summer Schools around the world. He has written more than 120 publications and is the author of review articles and books on masers, lasers and atomic clocks. His 2-volume book The Quantum Physics of Atomic Frequency Standards, (Editor: Adam Hilger1989), written with C. Audoin, is recognized as a main reference in the field. He has recently written with C. Tomescu a third volume of this book describing recent developments in the field (Taylor & Francis 2016). He is also the author of the book, The Universe, a challenge to the mind, (Imperial College Press 2011), describing in common language the physics of the universe we live in. Vanier is a Fellow of the Royal Society of Canada, of the American Physical Society and of the Institute of Electrical and Electronic Engineers. He has been the fortunate recipient of several awards for his contributions to the field of measurement science. He has remained active in science during his formal retirement and is currently Adjunct Professor at the Physics Department, University of Montreal.