Interior gap superfluidity in a two-component Fermi gas of atoms

TL;DR

This paper analyzes the properties of the interior gap superfluid phase in a two-component Fermi gas, exploring its energy gap, momentum distributions, and excitations, and discusses how it might be realized experimentally.

Contribution

It provides a nonperturbative variational analysis of the interior gap superfluid phase, detailing its features and potential experimental realization in optical traps.

Findings

Characterization of energy gap and excitations in the interior gap phase

Analysis of momentum distributions in the superfluid state

Discussion of experimental conditions for realization

Abstract

A new superfluid phase in Fermi matter, termed as "interior gap" (IG) or "breached pair", has been recently predicted by Liu and Wilczek [Phys.Rev.Lett. {\bf 90}, 047002 (2003)]. This results from pairing between fermions of two species having essentially different Fermi surfaces. Using a nonperturbative variational approach, we analyze the features, such as energy gap, momentum distributions, and elementary excitations associated with the predicted phase. We discuss possible realization of this phase in two-component Fermi gases in an optical trap.