Non-standard pairing in asymmetric trapped Fermi gases

TL;DR

This paper investigates unconventional pairing mechanisms in imbalanced ultracold Fermi gases confined in traps, extending the LOFF phase concept to finite systems using Bogoliubov-de Gennes equations.

Contribution

It introduces a generalized LOFF phase framework for finite trapped systems with population imbalance, solved via Bogoliubov-de Gennes equations.

Findings

Identification of non-standard pairing in asymmetric traps

Extension of LOFF phase to finite systems

Results consistent with generalized LOFF behavior

Abstract

We study an ultracold trapped Fermi gas of atoms in two hyperfine states with unequal populations. In this situation the usual BCS pairing is suppressed and non-standard pairing mechanisms become important. These are treated by solving the Bogoliubov-de Gennes equations, which at the same time correctly take into account the finite size of the trapped system. We find results which can be viewed as generalization of the LOFF phase to finite systems.