Exotic superfluid of trapped Fermi gases with spin-orbit coupling in dimensional crossover

TL;DR

This paper explores exotic superfluid phases in spin-orbit coupled Fermi gases across dimensional crossover, revealing topological states, Majorana modes, and diverse superfluid phases depending on tunneling strength.

Contribution

It introduces a mean-field analysis of phase diagrams in mixed dimensional Fermi gases with spin-orbit coupling, highlighting the emergence of topological and nodal superfluid phases.

Findings

Existence of topological states and Majorana modes in weak tunneling regimes.

Presence of nodal and gapped superfluid phases in strong tunneling regimes.

Topological pairing favored in quasi one dimension, nodal pairing in quasi two dimensions.

Abstract

We have studied the exotic superfluid phases of degenerated Fermi gases with spin-orbit coupling in a mixed dimensional system, where the motion of atoms are free in the x-direction and the tunneling between nearest tubes in the y-direction is permitted. Using the mean-field method, we obtain the phase diagrams of the system during the dimensional crossover between quasi one dimension to quasi two dimension. We find the existence of the topological state and Majorana edge mode in the weak tunneling case, and a rich phase diagram including two kinds of nodal superfluid phase and gapped superfluid phase in the opposite case. Our results show that topological pairing is favoured in quasi one dimension while nodal pairing state is favoured in quasi two dimension.