Pairing in a three component Fermi gas

TL;DR

This paper investigates pairing phenomena in a three-component degenerate Fermi gas, revealing unique finite-temperature phase transitions and the possibility of multiple critical temperatures, with implications for ultracold atom experiments.

Contribution

It provides a finite-temperature mean-field analysis of a three-component Fermi gas with unequal interactions and masses, uncovering novel phase transition behaviors.

Findings

Existence of a quantum phase transition at zero temperature between different pairing states.

Presence of two distinct critical temperatures at finite temperature.

Qualitative differences from two-component systems in phase transition behavior.

Abstract

We consider pairing in a three-component gas of degenerate fermions. In particular, we solve the finite temperature mean-field theory of an interacting gas for a system where both interaction strengths and fermion masses can be unequal. At zero temperature we find a a possibility of a quantum phase transition between states associated with pairing between different pairs of fermions. On the other hand, finite temperature behavior of the three-component system reveals some qualitative differences from the two-component gas: for a range of parameters it is possible to have two different critical temperatures. The lower one corresponds to a transition between different pairing channels, while the higher one corresponds to the usual superfluid-normal transition. We discuss how these phase transitions could be observed in ultracold gases of fermionic atoms.