Polarized fermions in the unitarity limit

Abstract

We consider a polarized Fermi gas in the unitarity limit. Results are calculated analytically up to next-to-leading order in an expansion about d=4 spatial dimensions. We find a first order transition from superfluid to normal phase. The critical chemical potential asymmetry for this phase transition is {delta}{mu}{sub c}=(2{mu}/{epsilon})(1-0.467{epsilon}), where {epsilon}=4-d is the expansion parameter and {mu} is the average chemical potential of the two fermion species. Stability of the superfluid phase in the presence of supercurrents is also studied.