The effect of spin-orbit interaction and attractive Coulomb potential on the magnetic properties of Ga$_{1-x}$Mn$_{x}$As

Abstract

We employ the dynamical mean-field approximation to study the magnetic properties of a model relevant for the dilute magnetic semiconductors. Our model includes the spin-orbit coupling on the hole bands, the exchange interaction, and the attractive Coulomb potential between the negatively charged magnetic ions and the itinerant holes. The inclusion of the Coulomb potential significantly renormalizes the exchange coupling and enhances the ferromagnetic transition temperature for a wide range of couplings. We also explore the effect of the spin-orbit interaction by using two different values of the ratio of the effective masses of the heavy and light holes. We show that in the regime of small $J_{c}$-$V$ the spin-orbit interaction enhances $T_{c}$, while for large enough values of $J_{c}$-$V$ magnetic frustration reduces $T_c$ to values comparable to the previously calculated strong coupling limit.