Topological superfluids on a lattice with non-Abelian gauge fields

TL;DR

This paper explores topological phases in two-component fermionic superfluids on a lattice with non-Abelian gauge fields, analyzing superfluidity breakdown, phase diagrams, and edge modes with efficient Chern number calculations.

Contribution

It provides a comprehensive topological phase diagram and a simple method for calculating Chern numbers, linking topological invariants to edge mode protection.

Findings

Identification of topological phases with large spin imbalance

Self-consistent calculation of superfluidity breakdown

Efficient method for Chern number computation

Abstract

Two-component fermionic superfluids on a lattice with an external non-Abelian gauge field give access to a variety of topological phases in presence of a sufficiently large spin imbalance. We address here the important issue of superfluidity breakdown induced by spin imbalance by a self-consistent calculation of the pairing gap, showing which of the predicted phases will be experimentally accessible. We present the full topological phase diagram, and we analyze the connection between Chern numbers and the existence of topologically protected and non-protected edge modes. The Chern numbers are calculated via a very efficient and simple method.