Quantum phases of interacting three-component fermions under the influence of spin-orbit coupling and Zeeman fields

TL;DR

This paper explores the rich quantum phase diagram of three-component fermions influenced by spin-orbit coupling and Zeeman fields, revealing topological transitions, gapless phases, and the transformation of order parameters.

Contribution

It provides a comprehensive classification of superfluid phases and identifies novel topological and Lifshitz-type transitions in a three-component fermionic system.

Findings

Identification of multiple Lifshitz-type topological transitions.

Existence of a quintuple point with four gapless phases converging.

Transformation of order parameters into momentum-dependent tensors.

Abstract

We describe the quantum phases of interacting three component fermions in the presence of spin-orbit coupling, as well as linear and quadratic Zeeman fields. We classify the emerging superfluid phases in terms of the loci of zeros of their quasi-particle excitation spectrum in momentum space, and we identify several Lifshitz-type topological transitions. In the particular case of vanishing quadratic Zeeman field, a quintuple point exists where four gapless superfluid phases with surface and line nodes converge into a fully gapped superfluid phase. Lastly, we also show that the simultaneous presence of spin-orbit and Zeeman fields transforms a momentum-independent scalar order parameter into an explicitly momentum-dependent tensor in the generalized helicity basis.