Effect of thermal fluctuations on spin degrees of freedom in spinor Bose-Einstein condensates

TL;DR

This paper investigates how thermal fluctuations influence the spin properties of rotating spinor Bose-Einstein condensates, revealing significant phase and magnetization fluctuations, especially in antiferromagnetic states, even at low temperatures.

Contribution

It provides a detailed analysis of thermal fluctuation effects on spinor BECs, highlighting differences between ferromagnetic and antiferromagnetic states.

Findings

Strong relative phase fluctuations due to weak spin interactions.

Significant local transverse magnetization fluctuations.

More pronounced fluctuations in antiferromagnetic states.

Abstract

We consider the effect of thermal fluctuations on rotating spinor F=1 condensates in axially-symmetric vortex phases, when all the three hyperfine states are populated. We show that the relative phase among different components of the order parameter can fluctuate strongly due to the weakness of the interaction in the spin channel. These fluctuations can be significant even at low temperatures. Fluctuations of relative phase lead to significant fluctuations of the local transverse magnetization of the condensate. We demonstrate that these fluctuations are much more pronounced for the antiferromagnetic state than for the ferromagnetic one.