Temperature dependence of the photoluminescence spectra of single crystals of CuInTe2

The temperature dependence of the photoluminescence spectra of ${\mathrm{CuInTe}}_{\mathrm{2}}$ has been studied between 10 and 120 K. From the analysis of the data, emissions due to free and bound excitons have been identified. The variation with $T$ of the free-exciton energy line is compared with the Manoogian–Woolley model for such a transition. An estimated value of the Debye temperature and the average phonon frequency are in good agreement with those reported from specific heat and reflectivity measurements, respectively. Using the existing theoretical models, binding and dissociation energy of excitons bound to ionized acceptors have been estimated. From the temperature dependence of the emission intensity of the bound exciton the activation energy is found to be $\text{(14±3)\hspace{0.17em}}\mathrm{meV}.$ This agrees quite well with the acceptor level of 15 meV reported in this compound.