Trapped Fermi gases with Rashba spin-orbit coupling in two dimensions

Abstract

We use the Bogoliubov-de Gennes formalism to analyze harmonically trapped Fermi gases with Rashba-type spin-orbit coupling in two dimensions. We consider both population-balanced and -imbalanced Fermi gases throughout the BCS-BEC evolution, and study the effects of spin-orbit coupling on the spontaneously induced countercirculating mass currents and the associated intrinsic angular momentum. In particular, we find that even a small spin-orbit coupling destabilizes Fulde-Ferrel-Larkin-Ovchinnikov (FFLO)-type spatially modulated superfluid phases as well as the phase-separated states against the polarized superfluid phase. We also show that the continuum of quasiparticle and quasihole excitation spectrum can be connected by zero, one or two discrete branches of interface modes, depending on the number of interfaces between a topologically trivial phase (e.g. locally unpolarized/low-polarized superfluid or spin-polarized normal) and a topologically nontrivial one (e.g. locally high-polarized superfluid) that may be present in a trapped system.

7 pages with 4 figures

References in corpus (4)

• Spin-Injection Spectroscopy of a Spin-Orbit Coupled Fermi Gas
• BCS-BEC crossover induced by a synthetic non-Abelian gauge field
• Topological Change of the Fermi Surface in Low Density Rashba Gases: Application to Superconductivity
• Role of the Majorana Fermion and the Edge Mode in Chiral Superfluidity near a p-Wave Feshbach Resonance

Cited by in corpus (7)

• The Fulde-Ferrell-Larkin-Ovchinnikov state for ultracold fermions in lattice and harmonic potentials: a review
• Spin-orbit coupling induced Fulde-Ferrell-Larkin-Ovchinnikov-like Cooper pairing and skyrmion-like polarization textures in trapped optical lattices
• Local suppression and enhancement of pairing condensate under rotation
• FFLO or Majorana superfluids: The fate of fermionic cold atoms in spin-orbit coupled optical lattices
• BCS-BEC crossover at finite temperature in spin-orbit coupled Fermi gases
• Spin evolution of cold atomic gases in SU(2)$\otimes$U(1) fields
• Temperature tuned Fermi surface topology and segmentation in non-centrosymmetric superconductors