Optical spectra and a tail in the density of states of the disordered solid solution ZnSe1?c Tec

A calculational scheme is presented to determine the density of states in the fluctuation tail for the disordered solid solution ZnSe_1−c Te_c at concentrations below the threshold for percolation over sublattice sites. Zero-phonon absorption and luminescence bands in the region of the exciton ground state are found using an approach developed earlier. Phonon coupling is taken into account, and vibronic absorption and luminescence bands are obtained. Experimental data are shown to be in a good agreement with the calculations. Fiz. Tverd. Tela (St. Petersburg) 40, 1420–1425 (August 1998)