Topological superfluids in two-dimensional Fermi gas with Rashba spin-orbit coupling

Abstract

The realization of spin-orbit coupling (SOC) in ultracold atoms has triggered an intensive exploring of topological superfluids in the degenerate Fermi gases based on mean-field theory, which has not yet been reported in experiments. Here, we demonstrate the topological phase transitions in the system via the numerically exact quantum Monte Carlo method. Without prior assumptions, our unbiased real-space calculation shows that spin-orbit coupling can stabilize an unconventional pairing in the weak SOC regime, in which the Fulde-Ferrell-Larkin-Ovchinnikov pairing coexists with the Bardeen-Cooper-Schrieffer pairing. Furthermore, we use the jumps in the spin polarization at the time-reversal invariant momenta to qualify the topological phase transition, where we find the critical exponent deviated from the mean-field theory. Our results pave the way for the searching of unconventional pairing and topological superfluids with degenerate Fermi gases.

13 pages, 5 figures

References in corpus (13)

• Computational complexity and fundamental limitations to fermionic quantum Monte Carlo simulations
• Spin-Injection Spectroscopy of a Spin-Orbit Coupled Fermi Gas
• Non-Abelian Topological Order in S-Wave Superfluids of Ultracold Fermionic Atoms
• Spin-Orbit Coupled Spinor Bose-Einstein Condensates
• A Bose-Einstein Condensate in a Uniform Light-induced Vector Potential
• Spin Hall effects for cold atoms in a light induced gauge potential
• Pairing states of a polarized Fermi gas trapped in a one-dimensional optical lattice
• Fulde-Ferrell-Larkin-Ovchinnikov superfluidity in one-dimensional optical lattices
• Density-Matrix Renormalization Group Study of Trapped Imbalanced Fermi Condensates
• Competing magnetic orders in a bilayer Hubbard model with ultracold atoms
• Strongly Correlated Topological Superconductors and Topological Phase Transitions via Green's Function
• Dynamical topological phases in quenched spin-orbit coupled degenerate Fermi gas
• Large Chern Number Topological Superfluids in Coupled Layer System