Fermi surface deformations and pairing in mixtures of dipolar and non-dipolar fermions

TL;DR

This paper investigates how dipolar interactions influence superfluid transition temperatures and Fermi surface shapes in mass-imbalanced fermionic mixtures, revealing that dipolar strength affects critical temperature and surface deformation.

Contribution

It provides the first analysis of Fermi surface deformations and critical temperature dependence in dipolar and non-dipolar fermion mixtures with mass imbalance.

Findings

Critical temperature varies with dipolar interaction strength.

Fermi surface deformations are observable in momentum distributions.

Dipolar interactions can enhance or suppress superfluid transition temperature.

Abstract

We study mass-imbalanced two-component Fermi mixtures, where one of the components consists of dipolar fermions. We specifically study the mass imbalances corresponding to the atomic ${}^{163}$Dy-${}^{40}$K and ${}^{53}$Cr-${}^{6}$Li mixtures. We study the onset of the $s$-wave superfluid phase, as a function of population imbalance and the dipolar interaction strength. We find the critical temperature and the Fermi surface deformations at the transition to depend on the dipolar interaction strength, where the critical temperature increases (decreases) with dipolar interaction strength for a majority (minority) of dipolar atoms. We present momentum distributions of both components where the Fermi surface deformations are visible.