Simulation of magnetoresistance in disordered ultracold atomic Bose gases

TL;DR

This paper theoretically investigates how disorder and synthetic magnetic fields affect magnetoresistance in two-dimensional ultracold Bose gases, revealing regimes of both positive and negative magneto-resistance.

Contribution

It introduces a theoretical framework for understanding magnetoresistance in disordered ultracold Bose gases under synthetic magnetic fields, highlighting different transport regimes.

Findings

Ballistic regime shows positive magneto-resistance.

Diffusive and localized regimes exhibit negative magneto-resistance.

Proposes experimental setups to observe these effects.

Abstract

Anderson localization was first investigated in the context of electrons in solids. One of the successes was in explaining the puzzle of negative magneto-resistance - as early as the 1940s it had been observed that electron diffusion rates in some materials can increase with the application of a magnetic field. Anderson localization has now been demonstrated in ultra-cold atomic gases. We present a theoretical study of the two-dimensional ultra-cold Bose gas in the presence of disorder, to which we apply a synthetic magnetic field. We demonstrate that, in the ballistic transport regime this leads to positive magneto-resistance and that, in the diffusive and strong localization regimes, can also lead to negative magneto-resistance. We propose experimental scenarios to observe these effects.