Dynamics of Impurity and Valence Bands in GaMnAs within the Dynamical Mean Field Approximation

Abstract

We calculate the density-of-states and the spectral function of GaMnAs within the dynamical mean-field approximation. Our model includes the competing effects of the strong spin-orbit coupling on the J=3/2 GaAs hole bands and the exchange interaction between the magnetic ions and the itinerant holes. We study the quasi-particle and impurity bands in the paramagnetic and ferromagnetic phases for different values of impurity-hole coupling at the Mn doping of x=0.05. By analyzing the anisotropic angular distribution of the impurity band carriers at T=0, we conclude that the carrier polarization is optimal when the carriers move along the direction parallel to the average magnetization.

6 pages, 4 figures