1212.0424 (Shang-Shun Zhang et al.)

Collective modes in spin-orbit coupled Fermi gases in the upper branch
of energy spectrum    [PDF]

Shang-Shun Zhang, Xiao-Lu Yu, Jinwu Ye, Wu-Ming Liu

We investigate the collective modes in the spin-orbit coupled Fermi gas with repulsive s-wave interaction. The interplay between spin-orbit coupling and atom-atom interactions plays the crucial role in the collective behavior of fermionic systems. In contrast with ordinary Fermi liquid, spin-orbit coupled Fermi gas has strongly correlated spin and density excitations which are fundamentally different from solid state systems. Within the scheme of random phase approximation, we classify collective modes based on the symmetry group and determine their properties via the poles of corresponding correlations functions. We also propose an experimental protocol for detecting these collective modes and discuss corresponding experimental signatures in the ultracold Fermi gases experiment.

View original: http://arxiv.org/abs/1212.0424