Superfluidity of spin-polarized 6Li

TL;DR

This paper investigates the conditions under which superfluidity can be observed in a spin-polarized $^6$Li atomic gas, identifying the phase diagram, critical temperature, and stability considerations for experimental realization.

Contribution

It provides a detailed analysis of the phase diagram and critical temperature for superfluidity in spin-polarized $^6$Li, highlighting optimal conditions for experimental observation.

Findings

Superfluidity can occur in the (meta)stable region at low densities.

Critical temperature at density 10^12 cm^{-3} is approximately 29 nK.

Superfluidity prospects are promising at magnetic fields above 10 T.

Abstract

We study the prospects for observing superfluidity in a spin-polarized atomic gas of $^6$Li atoms, using state-of-the-art interatomic potentials. We determine the spinodal line and show that a BCS transition to the superfluid state can indeed occur in the (meta)stable region of the phase diagram if the densities are sufficiently low. Moreover, for a total density of $10^{12}~cm^{-3}$, which still fulfills this requirement, we find a critical temperature of only $29~nK$. We also discuss the stability of the gas due to exchange and dipolar relaxation and conclude that the prospects for observing superfluidity in a magnetically trapped atomic $^6$Li gas are particularly promising for magnetic bias fields larger than $10~T$.