Effective medium approach for calculations of optical anisotropy in porous materials

We report on a generalized approach for the calculation of optical properties of various porous semiconductors. The presented methodology provides a simple method for predicting the type and value of optical anisotropy in different materials. Specifically, the cases of electrochemically etched mesoporous Si on (110)-oriented substrate and electrochemically-etched porous InP and GaAs materials on (100) substrates are considered. The optical anisotropy of mesoporous Si is explained and the dependence of the optical birefringence of this material on various material parameters is obtained. The optical anisotropy of porous InP and GaAs with crystallographic pores is predicted based on the presented model.