Spin-Orbit Coupled Fermi Gases across a Feshbach Resonance

In this Letter we study both ground state properties and the superfluid transition temperature of a spin-1/2 Fermi gas across a Feshbach resonance with a synthetic spin-orbit coupling, using the mean-field theory and the exact solution of two-body problem. We show that a strong spin-orbit coupling can significantly enhance the pairing gap for negative scattering length a(s), due to increased density of state at Fermi surface. Strong spin-orbit coupling can also significantly enhance the superfluid transition temperature T-c to a sizable fraction of Fermi temperature when a(s) less than or similar to 0, while it suppresses T-c slightly for positive a(s). The interaction energy and pair size at resonance are also discussed.