Dynamics of trapped two-component Fermi gas: Temperature dependence of the transition from collisionless to collisional regime

Abstract

We develop a numerical method to study the dynamics of a two-component atomic Fermi gas trapped inside a harmonic potential at temperature T well below the Fermi temperature [Formula Presented] We examine the transition from the collisionless to the collisional regime down to [Formula Presented] and find a good qualitative agreement with the experiments of B. DeMarco and D.S. Jin [Phys. Rev. Lett. 88, 040405 (2002)]. We demonstrate a twofold role of temperature on the collision rate and on the efficiency of collisions. In particular, we observe a hitherto unreported effect, namely, the transition to hydrodynamic behavior is shifted towards lower collision rates as temperature decreases. © 2003 The American Physical Society.