Teachers


		Visit to the Institute and Colloquium by Nobel Laureate
		Dr. Claude Cohen-Tannoudji, Nobel Laureate in Physics (1997), Professor, College de France and École Normale Supérieure, gave a colloquium lecture on “ Ultraprecise Atomic Clocks with Laser Cooled Atoms” at the P.C.Saxena Auditorium, IIT Bombay on 4th December 2006.
		Claude Cohen-Tannoudji shared the Nobel Prize for Physics in 1997 with Steven Chu and William D. Phillips. They received the award for their development of techniques that use laser light to cool atoms to extremely low temperatures. At such temperatures the atoms move slowly enough to be examined in detail. He has written 3 books and about 200 theoretical and experimental papers dealing with various problems of atomic physics and quantum optics. One of his books being a popular textbook is believed to be a bible for the students of Quantum Mechanics. Dr. Claude Cohen-Tannoudji had several interactions with the Research Scholars, Post-doctoral Associates and faculty, especially of the Physics Department. He visited the Department of Physics on the 4^th where he first met with faculty members and talked on various issues of education and research. He explained the research model in France, where specialised laboratories are operated by devoted scientific staff, while the faculty played the dual role of directing the research in the laboratory on the one hand and participating in the teaching programs in a separate institution. He was then presented with a poster session showcasing the activities of the Department. He made it a point to visit every poster and took keen interest in the explanations. He then attended an open house discussion with the research scholars of the Department and responded to technical queries on his discoveries but also fielded questions such as : ‘whether he had thought about winning the Nobel Prize when he had started physics’. Subsequently he visited several laboratories in the Department. At the Colloquium held at 4 pm he talked about the novel techniques developed by him and colleagues at the École Normale Supérieure. Speaking on atomic clocks he explained how the techniques pioneered by him have now reduced the possible error in an atomic clock to one second in 300 million years. His other contribution consists of techniques for cooling atoms to extremely low temperatures using a laser, reducing their random thermal motion to almost nothing. This has in turn led to more Nobel winning discoveries, such as the study of an exotic collective phase of atoms called the Bose-Einstein condensate.