Competition between pairing and tripling in one-dimensional fermions with coexistent s- and p-wave interactions

TL;DR

This paper explores the competition between pairing and tripling phenomena in one-dimensional fermionic systems with coexisting s- and p-wave interactions, revealing phase dominance depending on interaction strengths.

Contribution

It introduces a theoretical framework for analyzing in-medium three-body correlations and maps the phase diagram of pairing versus tripling phases in such systems.

Findings

Cooper tripling phase dominates at moderate interaction strengths.

Stable in-medium three-body states like Cooper triples are identified.

Phase diagram shows competition between pairing and tripling phases.

Abstract

We theoretically investigate in-medium two- and three-body correlations in one-dimensional two-component Fermi gases with coexistent even-parity s-wave and odd-parity p-wave interactions. We find the solutions of the stable in-medium three-body cluster states such as Cooper triple by solving the corresponding in-medium variational equations. We further feature the phase diagram consisting of the s- and p-wave Cooper pairing phase, and Cooper tripling phase, in the plane of s- and p-wave pairing strengths. The Cooper tripling phase dominates over the pairing phases when both s- and p-wave interactions are moderately strong.