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Title: Superfluid density and Berezinskii-Kosterlitz-Thouless transition of a spin-orbit-coupled Fulde-Ferrell superfluid

We theoretically investigate the superfluid density and Berezinskii-Kosterlitz-Thouless (BKT) transition of a two-dimensional Rashba spin-orbit-coupled atomic Fermi gas with both in-plane and out-of-plane Zeeman fields. It was recently predicted that, by tuning the two Zeeman fields, the system may exhibit different exotic Fulde-Ferrell (FF) superfluid phases, including the gapped FF, gapless FF, gapless topological FF, and gapped topological FF states. Due to the FF paring, we show that the superfluid density (tensor) of the system becomes anisotropic. When an in-plane Zeeman field is applied along the x direction, the tensor component along the y direction ns,yy is generally larger than ns,xx in most parameter space. At zero temperature, there is always a discontinuity jump in ns,xx as the system evolves from a gapped FF into a gapless FF state. With increasing temperature, such a jump is gradually washed out. The critical BKT temperature has been calculated as functions of the spin-orbit-coupling strength, interatomic interaction strength, and in-plane and out-of-plane Zeeman fields. We predict that the novel FF superfluid phases have a significant critical BKT temperature, typically at the order of 0.1TF, where TF is the Fermi degenerate temperature. Furthermore, their observation is within the reach of current experimental techniques inmore » cold-atom laboratories.« less
 [1] ;  [2] ;  [3] ;  [4] ;  [2]
  1. Swinburne Univ. of Technology, Melbourne (Australia); Tsinghua Univ., Beijing (China)
  2. Swinburne Univ. of Technology, Melbourne (Australia)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. Tsinghua Univ., Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (People's Republic of China); Tsinghua National Lab. for Information Science and Technology, Beijing (People's Republic of China)
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 1050-2947; PLRAAN
Grant/Contract Number:
FT140100003; FT130100815; DP140103231; DP140100637; 11175094; 91221205; AC52-06NA25396
Accepted Manuscript
Journal Name:
Physical Review. A
Additional Journal Information:
Journal Volume: 91; Journal Issue: 2; Journal ID: ISSN 1050-2947
American Physical Society (APS)
Research Org:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Org:
Country of Publication:
United States
74 ATOMIC AND MOLECULAR PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY Berezinskii-Kosterlitz-Thouless transition; Fulde-Ferrell superfluidity; spin-orbit coupling