Electron-Electron Interaction In One- And Two-Dimensional Ferromagnetic (Ga,Mn)As

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 two-dimensional films and a - 1/root T dependency in one-dimensional wires and is independent of an applied magnetic field. This behavior can be explained by the theory of electron-electron interaction.