Nobel laureate Claude Cohen-Tannoudji dies in Paris at age 93

The French physicist and Nobel laureate Claude Cohen-Tannoudji died in Paris on 22 October at the age of 93, Physics World reported. He was awarded the 1997 Nobel Prize in Physics for developing techniques to cool and trap neutral atoms with laser light. [1]

Physics World reported that Cohen-Tannoudji shared the 1997 Nobel Prize with Steven Chu and William Phillips. Chu and Phillips conducted experimental work in the 1980s demonstrating that photon collisions could reduce atomic gas temperatures below one millikelvin. This process was first understood through Doppler cooling, a mechanism where laser photon absorption slows atomic movement. However, experiments later showed that temperatures dropped far lower than Doppler cooling predicted. [1]

Cohen-Tannoudji attended the École Normale Supérieure in Paris between 1953 and 1957. He earned his doctorate in 1962 under the supervision of Alfred Kastler and Jean Brossel, studying the resonance fluorescence of excited atoms. He served as a full professor at the University of Paris from 1967 to 1973. His research subsequently demonstrated that laser cooling could bring atomic gases below the recoil temperature, expanding sub-Doppler cooling limits. [2][5]

The Nobel Prize in Physics is awarded annually by the Royal Swedish Academy of Sciences in Stockholm on 10 December. The techniques developed by Cohen-Tannoudji and his colleagues enabled scientists to isolate and manipulate individual quantum systems, advancing optical physics and quantum mechanics. [1][4]