The band structure of CuInTe 2 studied by optical reflectivity

CuInTe 2 is a semiconductor with high potential for use as a thermoelectric material and as the absorber in thin film solar cells. Studying the optical reflectivity spectra of CuInTe 2 single crystals resolves resonances at 1.054 eV and 1.072 eV, which are assigned to the A and B free excitons. Photoluminescence spectra exhibited a peak due to the A free exciton at 1.046 eV. Varshni coefficients were found for both excitons. Zero temperature bandgaps E gA = 1.060 eV and E gB = 1.078 eV were determined for the A and B valence sub-bands, respectively. The splitting due to crystal-field Δ CF and spin-orbit effects Δ SO were calculated as -26.3 meV and 610 meV, respectively, using the determined E gA and E gB and a literature value of E gC . © 2019 Author(s)