Critical temperature of pair condensation in a dilute Bose gas with spin-orbit coupling

TL;DR

This paper investigates the critical temperature for pair condensation in a dilute Bose gas with spin-orbit coupling, revealing it is significantly lower than the BEC transition temperature and highlighting anisotropic effective mass effects.

Contribution

It introduces a calculation of the critical temperature for pairing in a spin-orbit coupled Bose gas, accounting for anisotropic molecular effective mass.

Findings

Critical temperature is about eight times lower than BEC temperature.

Effective mass of molecules is anisotropic in momentum space.

Pairing state behavior differs from ideal Bose gas due to spin-orbit coupling.

Abstract

We study the Bardeen-Cooper-Shrieffer (BCS) pairing state of a two-component Bose gas with a symmetric spin-orbit coupling. In the dilute limit at low temperatures, this system is essentially a dilute gas of diatomic molecules. We compute the effective mass of the molecule and find that it is anisotropic in momentum space. The critical temperature of the pairing state is about eight times smaller than the Bose-Einstein condensation (BEC) transition temperature of an ideal Bose gas with the same density.