First-principles investigations of GaAs (112)-(2×2) surface reconstruction

We have investigated surface reconstructions of GaAs(112)A and GaAs(112)B surfaces using first-principles calculations. Ga-Ga and As-As dimmers are formed on GaAs(112)A and GaAs(112)B surface, respectively. The results show that the relaxed GaAs (112) A surface has lower surface free energy, 60.6 meV/Ų, while GaAs (112) B has 69.4 meV/Ų. The surface relaxation caused mainly from the top two layers. The analysis of surface electronic properties also has been demonstrated.