Elasticity-based approach of interfaces: Application to heteroepitaxy and hetero-systems

In this paper, we discuss the validity of the S-correlated theory of misfit -induced interface superstructures (MIIS) and nucleation centers for misfit dislocation network (NCMDN) by comparing its results with (i) those obtain ed by a fully self-consistent numerical approach and (ii) available experim ental results. Two main properties play an important role in the theory. Th e first one is the strain related S factor, which is the ratio of a linear function of the elastic constants over the material atomic density: this fa ctor can be identified from the standard equations of the elasticity theory which, in our approach. represents the basic background. This implies a re alistic lattice dynamic's model which enables to interpret the velocity of longitudinal, transverse and shear vibrational waves in solids. The second property, ns, is a geometrical parameter related to the extension of MIIS a nd to the lattice spacing of misfit dislocation network (MDN). We then appl y this theory to several hetero-systems and we demonstrate that it can be u sed to optimize heterointerfaces between host materials characterized by la rge lattice mismatch.