Gapless Topological Fulde-Ferrell Superfluidity in Spin-Orbit Coupled Fermi Gases
Gapless Topological Fulde-Ferrell Superfluidity in Spin-Orbit Coupled Fermi Gases
Topological superfluids usually refer to a superfluid state which is gapped in the bulk but metallic at the boundary. Here we report that a gapless, topologically nontrivial superfluid with an inhomogeneous Fulde-Ferrell pairing order parameter can emerge in a two-dimensional spin-orbit coupled Fermi gas, in the presence of both in-plane …