Magnetic susceptibility of diluted magnetic semiconductors at low carrier densities

Abstract

We calculate the static longitudinal and the transverse dynamic magnetic susceptibilities of (III,Mn)V diluted magnetic semiconductors, using the random phase approximation, for a simple impurity band model appropriate for the low charge carrier concentration regime. The magnetic susceptibilities are shown to depend sensitively on the amount of positional disorder of the Mn impurities. The results we obtain are consistent with previous studies of the spin wave spectrum and of the spatially inhomogeneous ferromagnetic state of these materials.