Thermal Glow Luminescence in Plastically Deformed KCl Crystal irradiated by X-Ray and Ultra Violet Light

An experimental study on the thermal glow luminescence in plastically deformed KCl crystals has been carried out. The thermal glow curves of plastically deformed crystals become simple and similar irrespective of the origin of crystals, in contrast with the case of “as-cleaved” crystals. In the case of ultra violet illumination at room temperature, glow curves consist of four peaks at 80°, 160°, 200° and 250°C. The intensity of glow peaks increases with deformation. The observed glows are attributed to the interaction of excitons with vacancy clusters. In X-rayed case, three peaks appear at 80°, 140° and 250°C. The peak at 250°C is very outstanding and is considered to be the luminescence due to the recombination of F and V 3 centers. Glows at 80° and 140°C are attributed to the recombination of released electrons from N and M centers with the trapped holes in V 2 centers. The recombination probability of 250°C-glow is enhanced very much by the perturbed field due to the plastic deformation.