Breached Pairing Superfluidity at Finite Temperature and Density

TL;DR

This paper analyzes fermion pairing at finite temperature and density with mismatched Fermi surfaces, revealing a unique breached pairing phase that exists at finite temperature and has a calabash-shaped region in the phase diagram.

Contribution

It introduces a comprehensive analysis of breached pairing superfluidity at finite temperature and density, highlighting its distinct phase structure compared to traditional BCS superfluidity.

Findings

Breached pairing phase exists at finite temperature and density.

The phase region has a calabash-like shape in the temperature-chemical potential plane.

The most probable formation temperature of the phase is finite, not zero.

Abstract

A general analysis on Fermion pairing at finite temperature and density between different species with mismatched Fermi surfaces is presented. Very different from the temperature effect of BCS phase, the recently found breached pairing phase resulted from density difference of the two species lies in a region with calabash-like shape in the $T-\mu$ plane, and the most probable temperature for the new phase's creation is finite but not zero.