Photoluminescence characterization of GaTe single crystals

Radiative recombination mechanisms in GaTe single crystals have been investigated as a function of temperature and excitation laser intensity in the energy region of 1.5–1.8 eV. Three emission bands have been observed located at 1.781 (A band), 1.735 (B band) and 1.575 eV (C band) at 10 K. A and B bands have been found to be strongly dependent on temperature while C band has been weakly dependent. The radiative recombination mechanisms of the A, B and C bands have been associated with the direct free exciton, bound-exciton and donor–acceptor pair (DAP) transitions from the temperature and excitation intensity dependencies of the PL intensities and peak energies of the emission bands.