Trapped phase-segregated Bose-Fermi mixtures and their collective excitations

Abstract

Recent progress in the field of ultracold gases has allowed for the creation of phase-segregated Bose-Fermi systems. We present a theoretical study of their collective excitations at zero temperature. As the fraction of fermion-to-boson particle number increases, the collective mode frequencies take values between those for a fully bosonic and those for a fully fermionic cloud, with damping in the intermediate region. This damping is caused by fermions which are resonantly driven at the interface. © 2009 The American Physical Society.