Colloquium on June 25, 2007

Patricio Leboeuf, LPTMS Orsay

Interacting bosons in random media: Superfluidity versus Anderson localization

We consider the general transport properties of a guided beam of Bose-Einstein condensed particles (an "atom laser") relative to a scattering potential. In the particular case of a disordered medium, interaction effects lead to two distinct stationary flows. One is subsonic and corresponds to superfluid motion. The other one is supersonic, dissipative and shows Anderson localization. We also explain the disappearance of the supersonic stationary flow for large extensions of the disordered potential.