Fundamental absorption edge in the semiconductor CdInGaS4at high temperatures

Abstract
The optical absorption of CdInGaS4 single crystals has been measured in the 2.0-3.0 eV photon energy range and at temperatures from 300K to 800K. The interband gap for the indirect allowed transition was found to have a thermal coefficient, dEg/dT, of -8.0*10-4eV K-1. The preliminary calculations suggest that the electron-phonon interaction is dominant in the temperature dependence of the energy gap in this material.