Cadmium Sulfide with Silver Activator

Abstract

Further experimental evidence is presented in connection with a model which has been proposed by Lambe and Klick for CdS(Ag). In this model, the silver activator is assumed to give rise to a level which is approximately 0.4 ev below the conduction band, and that luminescence occurs when an electron in such an activator level recombines with a free hole. It is shown that irradiation in the 1μ infrared region stimulates luminescence by generating free holes, while also causing well known quenching effects in photocurrent. It is also shown that 3μ irradiation gives rise to photoconduction by exciting electrons from the activator levels into the conduction band. The proposed model indicates that irradiation in the 3μ region should quench luminescence by removing electrons from activator levels, and this is found experimentally. These experiments further substantiate the proposed model for CdS(Ag).