Spin drag in noncondensed Bose gases

TL;DR

This paper explores how time-dependent magnetic fields induce spin motive forces and spin drag in noncondensed Bose gases, proposing experimental observation in toroidal traps and analyzing temperature-dependent effects.

Contribution

It introduces a transport coefficient for spin drag in Bose gases, analogous to electronic systems, highlighting Bose enhancement effects at lower temperatures.

Findings

Spin motive forces and spin drag are induced by magnetic fields.

The transport coefficient increases as temperature decreases.

Heating effects on the system are analyzed.

Abstract

We show how time-dependent magnetic fields lead to spin motive forces and spin drag in a spinor Bose gas. We propose to observe these effects in a toroidal trap and analyze this particular proposal in some detail. In the linear-response regime we define a transport coefficient that is analogous to the usual drag resistivity in electron bilayer systems. Due to Bose enhancement of atom-atom scattering, this coefficient strongly increases as temperature is lowered. We also investigate the effects of heating.