Electron-electron interaction in 2D and 1D ferromagnetic (Ga,Mn)As

TL;DR

This paper studies how electron-electron interactions affect magnetotransport in high-quality ferromagnetic (Ga,Mn)As films and wires, revealing distinct temperature dependencies in 2D and 1D structures that are unaffected by magnetic fields.

Contribution

It demonstrates the dimensional dependence of electron-electron interaction effects on conductivity in ferromagnetic (Ga,Mn)As, supported by experimental data down to 20 mK.

Findings

Conductivity decreases logarithmically in 2D films at low temperatures.

Conductivity decreases as -1/√T in 1D wires at low temperatures.

Behavior is independent of applied magnetic field, consistent with electron-electron interaction theory.

Abstract

We investigated the magnetotransport in high quality ferromagnetic (Ga,Mn)As films and wires. At low temperature the conductivity decreases with decreasing temperature without saturation down to 20 mK. Here we show, that the conductivity decrease follows a ln($T/T_0$) dependency in 2D films and a $-1/\sqrt{T}$ dependency in 1D wires and is independent of an applied magnetic field. This behavior can be explained by the theory of electron-electron interaction.