Three-component Fulde-Ferrell superfluids in a two-dimensional Fermi gas with spin-orbit coupling

Abstract

We investigate the pairing physics of a three-component spin-orbit coupled Fermi gas in two spatial dimensions. The three atomic hyperfine states of the system are coupled by the recently realized synthetic spin-orbit coupling (SOC), which mixes different hyperfine states into helicity branches in a momentum-dependent manner. As a consequence, the interplay of spin-orbit coupling and the hyperfine-state dependent interactions leads to the emergence of Fulde-Ferrell (FF) pairing states with finite center-of-mass momenta even in the absence of the Fermi-surface asymmetry that is usually mandatory to stabilize an SOC-induced FF state. We show that, for different combinations of spin-dependent interactions, the ground state of the system can either be the conventional Bardeen-Cooper-Schrieffer pairing state with zero center-of-mass momentum or be the FF pairing states. Of particular interest here is the existence of a three-component FF pairing state in which every two out of the three components form FF pairing. We map out the phase diagram of the system and characterize the properties of the three-component FF state, such as the order parameters, the gapless contours and the momentum distributions. Based on these results, we discuss possible experimental detection schemes for the interesting pairing states in the system.

8 pages, 7 figures, updated references, published version

References in corpus (8)

• Spin-Injection Spectroscopy of a Spin-Orbit Coupled Fermi Gas
• Degenerate Quantum Gases with Spin-Orbit Coupling
• A Bose-Einstein Condensate in a Uniform Light-induced Vector Potential
• Unconventional superfluid in a two-dimensional Fermi gas with anisotropic spin-orbit coupling and Zeeman fields
• Pairing Superfluidity in Spin-Orbit Coupled Ultracold Fermi Gases
• Topological Fulde-Ferrell Superfluids of a Spin-Orbit Coupled Fermi Gas
• Three-component Ultracold Fermi Gases with Spin-Orbit Coupling
• Three-component topological superfluid in one-dimensional Fermi gases with spin-orbit coupling

Cited by in corpus (6)

• Strongly interacting bosons on a three-leg ladder in the presence of a homogeneous flux
• Light-induced half-quantized Hall effect and axion insulator
• Three-body correlations in a two-dimensional SU(3) Fermi gas
• Kinked linear response from non-Hermitian cold-atom pumping
• Nonlinear Hall effects with an exceptional ring
• Fulde-Ferrell superfluids in an asymmetric three-component Fermi Gas