Contribution of the Internal Field to the Anisotropic Optical Reflectance of GaP(110)

This article presents the theory of optical reflection from thin slabs of GaP(110) by means of the discrete dipole model and focusses especially upon the possible implications of this model for the surface induced optical anisotropy. The reflectance of a semi-infinite sample is extracted from slab calculations and compared with experiments. We find that the internal field has a very important role in determining the surface induced optical anisotropy. We also show that the surface sensitivity of such experiments can be estimated to be about five monolayers