Exoelectron Emission during the Thermal Annihilation of VK Centers in Pure and Cu-Doped NaCl

Abstract

Thermally stimulated exoelectron emission (TSEE) in pure and Cu-doped NaCl crystals, which are cleaved in a clean high vacuum and X-irradiated at 77 K, is measured simultaneously with thermoluminescence (TL). The emission and absorption spectra, the decay of the TSEE and TL intensities and the change in the glow curves by the F-light stimulation, are also measured. The main TSEE glow peaks are ascribed to reaction of color centers as well as the TL glow peaks. Among them, the TSEE glow peak at about 160 K in these crystals is due to the diffusion of V K centers and the subsequent reaction of them with F' centers. The release-process of the electrons in this case may be interpreted in terms of a kind of Auger effect.