Electron correlation effects on the hydrogen passivation of Mn(x)Ga(1-x)As dilute magnetic semiconductors

Atomic hydrogen diffuses in semiconductor lattices and binds to impurities by forming complexes that can lead to a full neutralization of the impurity effects. In the present paper, the structural, vibrational, electronic, and magnetic properties of complexes formed by H in the MnxGa1–xAs (x=0.03) dilute magnetic semiconductor have been investigated by using first-principles density-functional theory theoretical methods both in gradient-corrected spin-density (sigma-GGA) and Hubbard U(sigma-GGA+U) approximations. The results account for recent experimental findings showing a H passivation of the electronic and magnetic properties of Mn in GaAs. Most importantly, they show that electron correlation has crucial effects on the properties of H-Mn complexes.