Dissipation and Localization of an Oscillating Condensate with Random Disorder
Che-hsiu Hsueh1*, Wen Chin Wu1
1Department of Physics, National Taiwan Normal University, Taipei, Taiwan
* Presenter:Che-hsiu Hsueh, email:chhsueh7@gmail.com
Based on the Gross-Pitaevskii equation approach, we theoretically re-examined the experiment of Hulet et al. [Phys. Rev. A 82, 033603 (2010)] for an oscillating condensate with random disorder. In agreement with previous studies, when the center-of-mass velocity v0 is larger than the sound velocity c0 of quasiparticles (QP), the decaying of the oscillating condensate amplitude is mainly caused by the dissipation of the kinetic energy which is transformed to the production of QPs assisted by the random disorder -- in accordance with Landau criterion. However, when v0 << c0 in which no more QPs are produced, through the study of time-of-flight (TOF) of condensate wave function we argue that the condensate falls into the phenomenon of Anderson localization. This differs from the conclusion of previous studies. It is thus suggested that TOF image should be taken for the same experiment when v0 << c0.

Keywords: Bose-Einstein condensate, disorder, dissipation, Anderson localization, Gross-Pitaevskii equation