Optical spectra and energy band structure of single crystalline CuGaS2 and CuInS2

Abstract

The anisotropic spectra of edge absorption, reflection, and photoconductivity of the monoclinic ZnP2, and ZnA2, crystals have been experimentally investigated at 293 and 77 °K. The group-theoretical calculations of selection rules for interband transitions and the dispersion relaxation are discussed. Energy band structure models at the band gap are proposed on the basis of known theoretical and obtained experimental data. Polarization investigations allowed to determine the subband symmetry responsible for transitions in the energy range from 1 to 12.5 eV.