Juan Pablo Paz

The so called « fluctuation theorems » are one of the most important results in non equilibrium thermodynamics obtained during the last decades. They connect the behavior of a system evolving far away from equilibrium with certain properties of thermal equilibrium states of the same system. The work probability distribution plays a major role in such theorems and its measurement attracted a lot of interest recently. In this talk I will review a new strategy for measuring work on a quantum system which evolves out of equilibrium. I will also show how these ideas have been recently implemented in an experiment which enabled us to directly sample the work probability distribution. The « quantum work meter » I will present, built with an ensemble of cold Rubidium atoms manipulated by an atom chip, enabled us to perform a direct test of the most notable fluctuation theorem: the Jarzynski identity.