POLARIZATION-DEPENDENT REFRACTIVE-INDEX CHANGE INDUCED BY SUPERLATTICE DISORDERING

A model of the polarization-dependent refractive-index change that acc ompanies superlattice disordering is proposed for the first time. Calc ulated results agree well with experimental results in terms of the am ount and direction of the refractive-index changes. In the GaAs-AlAs s ystem, a simple diffusion model that considers the diffusion of group III atoms explains the experimental results. In a InGaAs-InP system, i t is assumed that group V atoms mainly induce disordering, and the dif ference between the diffusion constant in wells and that in barriers i s taken into account. The refractive-index changes induced by superlat tice disordering are useful for fabricating polarization control devic es and integrated optical circuits.