Curie temperatures of

Curie temperatures of the diluted magnetic semiconductors $\chem{(Ga, Mn)As}$, ($\chem{Ga}$, $\chem{Mn}$)$\chem{N}$, $\chem{(Ga, Cr)As}$ and $\chem{(Ga, Cr)N}$ are evaluated from first principles. The electronic structure is calculated in the local spin density approximation by using the Korringa-Kohn-Rostoker method combined with the coherent potential approximation to describe the substitutional and spin disorder. From the total energy differences between the ferromagnetic state and the spin-glass state, realistic estimations of Curie temperatures are achieved by using a mapping on the Heisenberg model in the mean-field approximation. Effects of additional carrier doping treatments are also investigated. Very large Curie temperatures are obtained, lying above room temperature for $\chem{(Ga, Mn)N}$, $\chem{(Ga, Cr)As}$ and $\chem{(Ga, Cr)N}$. Upon hole doping the Curie temperature of $\chem{(Ga, Mn)N}$ further increases, while $\chem{(Ga, Mn)As}$ shows a plateau behavior