2014/02/28 by Ye Cao, Shu-Hao Zou, Xia-Ji Liu +3 · 1 citation
Physics and Astronomy · #cond-mat.quant-gas
paper · pdf · doi:10.1103/physrevlett.113.115302
published as Phys. Rev. Lett. 113, 115302 (2014) · 5 pages, 5 figures; add the results on the critical BKT temperature and superfluid density, as well as the discussion on the robustness of the chiral edge states against disorder
arxiv created 2014/07/16 · arxiv updated 2014/10/07
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 non-trivial superfluid with inhomogeneous Fulde-Ferrell pairing order parameter can emerge in a two-dimensional spin-orbit coupled Fermi gas, in the presence of both in-plane and out-of-plane Zeeman fields. The Fulde-Ferrell pairing - induced by the spin-orbit coupling and in-plane Zeeman field - is responsible for this gapless feature. This exotic superfluid has a significant Berezinskii-Kosterlitz-Thouless (BKT) transition temperature and has robust Majorana edge modes against disorder owing to its topological nature.