Calculation of electronic band of complex superlattice with an empirical spds∗ tight-binding model

Complex superlattice, i.e. with a period consisting of more than two different layers has generated intense interest since the discovery of the superlattice. But since there are too many configurations to pick out the needed one, and for the limit of crystal growth technique, they were not well studied. In this paper, based on an empirical spds∗ tight-binding model, electronic and optical properties of complex superlattices are calculated. Useful empirical parameters corresponding to the congregation of one kind of cations are defined. The energy bands, especially the lowest conduction band and the top of the valence band, have a simple trend with the change of the empirical parameter. Type-I to type-II transition problems are also discussed in this paper.