A structural and electronic property of GaAs and Ge and super-lattice GaAs / Ge (001)

The structural and electronic properties of the bulk GaAs and Ge semiconductor and the band offsets for the GaAs/Ge and AsGa-Ge interfaces are investigated by density functional theory (DFT). This calculation has shown that the lattice parameter is underestimated by the local density (LDA) approximation and overestimated by the generalized gradient approximation (GGA). An opposite behavior is observed for the bulk modulus B0. Concern, the super-lattice GaAs/Ge (001), studied in our work, we found that the substitution of the atom of the interface affects the discontinuity of the VBO valence band, which is mainly due to the different electronic charges accumulated in the interfaces.