Simulation of optical function for phosphide crystals following the DFT band structure calculations

The electronic and optical functions of zinc-blende III-phosphide (BP, AlP, GaP and InP) are studied based on the first-principles calculations. The optical functions, including the complex dielectric function, optical reflectivity, refractive index, extinction coefficient, absorption efficient and electron energy loss, are discussed for radiation up to 36 eV by analyzing the energy band structures and density of states calculated. The common trends and the differences among the four III-phosphide compounds are presented. We also have explained the origin of the spectral peaks on the basis of the electronic band structures. Calculated optical functions indicate that these zinc-blende III-phosphide can serve as shielding devices for ultraviolet radiation. Our results of the electronic and optical properties are in agreement with the experimental data when available, in other case they can be considered as predictions.