Thermoluminescence and thermally stimulated currents in quartz

Abstract

Processes of excitation and recombination in quartz were investigated. Specimens were natural Brazilian, and synthetic Ge-doped crystals. Excitation was by X-rays or 5 MeV electrons. TL measurements included spectra of emission, bleaching and re-excitation. TC and optical absorption were also measured. Most TL peaks were accompanied by TC peaks. Samples showing strong TL had generally weak TC and vice versa. TL spectra of all samples showed a band at 370 nm. Some peaks, mainly at temperatures below 300° K often emitted in the blue-green. TL peaks were bleachable optically, 300 nm light being most effective. TC peaks were unaffected by UV, indicating that luminescence centers and not trapped electrons were involved. TL peaks could be re-excited by UV light (290 nm). These and other results are discussed and conclusions as to energy levels and transitions involved are drawn.