Impact of inhomogeneous strain on the valence band structures of Ge-Si core-shell nanowires

We report on a theoretical study of the valence band structures of germanium-silicon core-shell nanowires based on a 6times6 kldrp model. We take into account the inhomogeneous strain effects induced by the lattice mismatches between germanium and silicon. We find that the top subband ends drift back to Gamma point, and the effective masses of more subbands begin to decrease when the shell thickness increases.