Temperature dependence of the fundamental absorption edge in CuInTe2

Abstract

The temperature dependence of the energy gap EG and the binding energy Rx of free excitons in single crystals of CuInTe2 have been calculated using Elliot’s model. The samples were prepared by the method of tellurization of stoichiometric Cu and In in liquid phase and the vertical Bridgman technique. The value of Rx around 4 meV agrees quite well with that deduced from the effective mass approximation. The variation of EG with temperature is compared with the empirical model proposed by A. Mannogian and J. C. Woolley [Can. J. Phys. 62, 285 (1984)]. The estimated value of the Debye temperature is in agreement with ΘD=191.4 K reported from specific heat measurements.