Counterflow of spontaneous mass currents in trapped spin-orbit coupled Fermi gases

Abstract

We use the Bogoliubov-de Gennes formalism and study the ground-state phases of trapped spin-orbit coupled Fermi gases in two dimensions. Our main finding is that the presence of a symmetric (Rashba type) spin-orbit coupling spontaneously induces counterflowing mass currents in the vicinity of the trap edge, i.e. $\uparrow$ and $\downarrow$ particles circulate in opposite directions with equal speed. These currents flow even in noninteracting systems, but their strength decreases toward the molecular BEC limit, which can be achieved either by increasing the spin-orbit coupling or the interaction strength. These currents are also quite robust against the effects of asymmetric spin-orbit couplings in $x$ and $y$ directions, gradually reducing to zero as the spin-orbit coupling becomes one dimensional. We compare our results with those of chiral p-wave superfluids/superconductors.

6 pages with 4 figures; to appear in PRA

References in corpus (16)

• A Bose-Einstein Condensate in a Uniform Light-induced Vector Potential
• Spin-Orbit Coupled Quantum Gases
• p-wave Feshbach molecules
• BCS-BEC crossover induced by a synthetic non-Abelian gauge field
• BCS-BEC Crossover in 2D Fermi Gases with Rashba Spin-Orbit Coupling
• Topological superfluid in a trapped two-dimensional polarized Fermi gas with spin-orbit coupling
• Role of the Majorana Fermion and the Edge Mode in Chiral Superfluidity near a p-Wave Feshbach Resonance
• Rashba spin-orbit coupled atomic Fermi gases
• Tuning the Tricritical Point with Spin-orbit Coupling in Polarized Fermionic Condensates
• Opposite effect of spin-orbit coupling on condensation and superfluidity
• Mass flows and angular momentum density for $p_x+i{p}_y$ paired fermions in a harmonic trap
• Quantum phases of atomic Fermi gases with anisotropic spin-orbit coupling
• Trapped fermions in a synthetic non-Abelian gauge field
• Population imbalanced fermions in harmonically trapped optical lattices
• Vortex line in spin-orbit coupled atomic Fermi gases
• Lifetime of angular momentum in a rotating strongly interacting Fermi gas

Cited by in corpus (4)

• Unconventional states of bosons with synthetic spin-orbit coupling
• Spin-orbit coupling induced Fulde-Ferrell-Larkin-Ovchinnikov-like Cooper pairing and skyrmion-like polarization textures in trapped optical lattices
• Short range asymptotic behavior of the wave-functions of interacting spin-half fermionic atoms with spin-orbit coupling: a model study
• Trapped Fermi gases with Rashba spin-orbit coupling in two dimensions