Superfluid Phases of Dipolar Fermions in Harmonically Trapped Optical Lattices

الأصل · EN

We describe the emergence of superfluid phases of ultracold dipolar fermions in optical lattices for two-dimensional systems. Considering the many-body screening of dipolar interactions at intermediate and larger filling factors, we show that several superfluid phases with distinct pairing symmetries naturally arise in the singlet channel: local s-wave (sl), extended s-wave (se), d-wave (d) or time-reversal-symmetry breaking (sl + se ± id)-wave. We obtain the temperature versus filling factor phase diagram and show that d-wave pairing is favored near half-filling, that (sl + se)-wave is favored near zero or full filling, and that time-reversal-breaking (sl + se ± id)-wave is favored in between. The inclusion of a harmonic trap reveals that a sequence of phases can coexist in the cloud depending on the filling factor at the center of the trap. Most notably in the spatial region where the (sl + se ± id)-wave superfluid occurs, spontaneous currents are generated, and may be detected using velocity sensitive Bragg spectroscopy.