Photoelectronic Properties of CdGa₂S₄ Single Crystals

Experimental investigations of the photoelectric properties of CdGa2S4 single crystals were carried out. The study examined the temperature dependence of the photocurrent (within the 110–420 K range), as well as the spectral dependence and transient characteristics of optical quenching at T = 300 K. Optical quenching of the photocurrent was observed within a secondary light beam energy range of 0.6 - 2.49 eV. Measurements revealed energy levels at Ec - 0.21 eV, Ec - 0.42 eV, and Ec - 1.06 eV, as well as sensitizing levels at Ev + 0.89 eV. The decrease in photocurrent at temperatures above 300 K is attributed to thermal quenching. Both optical and thermal quenching of photoconductivity in CdGa2S4 crystals are ascribed to changes in the charge state and exchange dynamics of sensitizing and recombination centers.