Relaxation of photoexcited silver chloride

Relocalization of excess carriers from shallow levels to deep levels is observed in addition to carrier recombination during thermal relaxation of photoexcited silver chloride. Experimental dependences of the parameters of the photostimulated luminescence flash (released light sum and kinetic coefficient) on the relaxation time and temperature are explained within a three-level model including a recombination (luminescence) level, a deep level with energy ΔE ≈ 1.8 eV, and a shallow level with energy ΔE ≈ 0.03 eV with respect to the conduction-band bottom. It was shown that Ag+ ion adsorption caused a decrease in the relocalization activation energy from 0.17 to 0.03 eV, which is attributed to the surface nature of the centers responsible for the initial relaxation stage. © Pleiades Publishing, Inc., 2006.