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

Daniel Neumaier, Markus Schlapps, Ursula Wurstbauer, Janusz Sadowski, Matthias Reinwald, Werner Wegscheider, Dieter Weiss

Published 2007-11-21, updated 2007-11-22Version 2

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.