Atomic and electronic structure of the CdTe(001) surface: LDA andGWcalculations

The CdTe(001) surface has been studied theoretically by means of the local-density approximation (LDA) to the density-functional theory and the many-body GW approach. Within the LDA method the minimum-energy geometry is determined for several reconstruction models and a phase diagram of stable structures is established. For the most stable reconstruction model over a large range of ambient conditions, the c(2×2) Cd-vacancy reconstruction, the surface electronic structure has been determined by means of the analysis of the spatial behavior of Kohn-Sham orbitals and the local density of states. In addition, self-energy corrections to the energies of the surface states are determined using the GW method. The spin-orbit interaction, which is important in CdTe, is perturbatively included in calculations.