Hopping and low-temperature photoluminescence in solid solutions and amorphous semiconductors

Abstract

A quantitative theory of low-temperature interpair radiative recombination of localized carriers in amorphous semiconductors has been developed. An allowance is made for the partial populations of the tail states and the exponential dependence of the hopping and recombination rates on the distance between the localization centres. The theory has been modified to analyse the energy distribution of excitons localized by composition fluctuations in semiconductor solid solutions. The position of the photoluminescence peak and its shift with increase in excitation intensity are related to the parameters of the localized carriers. A comparison between theory and experiment is carried out for CdS_1–xSe_x solid solutions.