Structures and electronic states of Mg incorporated into InN surfaces: First-principles pseudopotential calculations

Structures and electronic states of Mg incorporated into InN surfaces in various orientations including nonpolar (10 (1) over bar0) and (11 (2) over bar0) as well as polar (0001) and (000 (1) over bar) surfaces are systematically investigated by performing first-principles pseudopotential calculations. Employing a thermodynamic approach, the calculated surface energies demonstrate characteristic features in the stability of Mg-incorporated surfaces depending on the growth condition. The calculated density of states also predict that regardless of surface orientation, Mg acceptors at the surface are compensated by the extra electrons originating from the surface states of In layers in bare surfaces.