Investigation of inversion-asymmetry effects on the band structure of Sn 1Ge n superlattices

Abstract

We have studied the detailed band structure near the Γ point of Sn 1Ge 3 superlattices grown on Ge (001) and (111) using the linear muffin-tin-orbital method. The inversion asymmetry leads to linear spin splittings and different effective masses for the spin-split states. These superlattices are predicted to have large interband optical matrix elements. The variation of the spin splitting and band gap with the number of Ge layers has also been investigated using the empirical tight-binding method. The band-edge properties are correlated with the nature of the superlattice states in both real and wave-vector space and are compared with those of GaAs AlAs and Si Ge superlattices.