Influence of the interface spacing on the interface states in heterojunctions between monatomic semiconductors

The influence of small and moderate deformations of the interface spacing on the existence of interface states is discussed on the basis of a generalised one-dimensional model and by using a scattering theoretical method. The method applies equally well to both shrinkage and dilatation of the interface spacing and covers all examples from the ideal undeformed heterojunction to the extreme deformation discussed recently. The essential conditions for the existence of interface states are derived and the numerical analysis performed is used to examine several interesting examples.