Claude Cohen-Tannoudji (born April 1, 1933) is a French physicist working at the École Normale Supérieure in Paris, France, where he has also studied physics.

Cohen-Tannoudji was born in Constantine to Algerian Jewish parents, when Algeria was still part of France. After primary and secondary studies in Algiers, Cohen-Tannoudji left Algeria for Paris to attend the École normale supérieure. Lectures were given by Henri Cartan, Laurent Schwartz or Alfred Kastler. In 1958 he married Jacqueline, a high school teacher, who gave birth to three of his children. Cohen-Tannoudji left the laboratories of the École Normale to perform his military service for 28 months (longer that usual because of the Algeria war). In 1960 he returned to his institution to work on a doctorate degree, which he obtained at the end of 1962.

After his thesis, he started teaching quantum mechanics at the Paris university. His lecture notes were the basis of the popular textbook Mécanique quantique he wrote with two of his colleagues. He also continued his research work on atom-photon interactions, and his group developed the dressed atom formalism.

In 1973, he became a professor at the Collège de France. In the early 1980s, he started to lecture on radiative forces on atoms in laser light fields. He also formed a laboratory there with Alain Aspect and Jean Dalibard to study laser cooling and trapping. His work there eventually lead to the physics Nobel Prize of 1997 for the development of methods to cool and trap atoms with laser light, shared with Steven Chu and William Daniel Phillips.

(From Wikipedia.org)