Electron-electron interaction in doped GaAs at high magnetic field

TL;DR

This paper investigates how high magnetic fields affect electron-electron interactions in doped GaAs, revealing an inversion in conductivity behavior and suppression of interaction corrections consistent with theoretical predictions.

Contribution

It provides experimental validation of the predicted inversion of conductivity correction due to Coulomb interactions at high magnetic fields in doped GaAs.

Findings

Inversion of low-temperature conductivity dependence at Wct=1

Suppression of the Hartree interaction correction for Wct>1

Total correction remains logarithmic but is significantly reduced

Abstract

We observe an inversion of the low temperature dependence for the conductivity of doped GaAs by application of a magnetic field. This inversion happens when Wct = 1, as predicted by Houghton (PRB25, 2196, 1982) for the correction to conductivity due to screened Coulomb repulsion in the diffusive regime. This correction follows the oscillating behavior of the transport elastic time entering the Shubnikov-de Haas regime. For Wct > 1, we observe that the Hartree part of the interaction correction is suppressed. Moreover, the total correction seems strongly reduced although its dependence stays logarithmic.