The effect of anisotropic exchange interactions and short-range phenomena on superfluidity in a homogeneous dipolar Fermi gas

TL;DR

This paper introduces a numerical method to accurately compute the superfluid transition temperature in dipolar Fermi gases, revealing that short-range effects and anisotropic interactions greatly suppress superfluidity at high densities.

Contribution

A new numerical approach for precise Tc calculation in dipolar Fermi gases, accounting for anisotropic exchange and short-range phenomena, challenging previous estimates.

Findings

Superfluid transition temperature is much lower than previously thought at high densities.

Dimerisation of atoms and molecules inhibits superfluid formation.

Short-range effects significantly impact superfluid properties in dipolar gases.

Abstract

We develop a simple numerical method that allows us to calculate the Bardeen-Cooper-Schriefer (BCS) superfluid transition temperature (Tc) precisely for any interaction potential. We apply it to a polarised, ultracold Fermi gas with long-range, anisotropic, dipolar interactions and include the effects of anisotropic exchange interactions. We pay particular attention to the short-range behaviour of dipolar gasses and re-examine current renormalisation methods. In particular, we find that dimerisation of both atoms and molecules significantly hampers the formation of a superfluid. The end result is that at high density/interaction strengths, we find Tc is orders of magnitude lower than previous calculations.