Ab initio investigation of the CdTe (001) surface

Based on first-principles density functional pseudopotential calculations, the CdTe (001) surface has been studied. Atomic configurations of different reconstructions are obtained with good accuracy. This reveals the efficiency of the force calculation for the surface relaxations. The surface energies were calculated on relaxed surface slabs as a function of the chemical potentials. The main result is that the energy of the Te-terminated dimerized surface with a (2 × 1) reconstruction is larger than the Cd-terminated c(2×2)c(2×2) reconstructed surface. This is in agreement with what was suspected by the equilibrium model introduced by F. Tinjod et al., which explains the formation of the quantum dots in CdTe/ZnTe superstructures.