A study of photostimulated thermoluminescence in C-doped alpha -Al2O3crystals

Abstract

The effects of ultraviolet light on alpha -Al₂O₃:C crystals were studied. Thermoluminescence, X-ray-induced luminescence and photostimulated thermoluminescence were investigated. Emission as well as stimulation spectra were measured. The main thermoluminescence and photostimulated thermoluminescence peaks appeared in both types of crystals at the same temperature of 180 degrees C and with the same thermal activation energy of 1.12 eV. The 410 nm band was dominant in C-doped crystals, while the 325 nm band was the main one in pure samples. Al₂O₃:C crystals which had previously been exposed to ionizing radiation and heated only to 500 degrees C, were found to be sensitive to extremely low doses of monochromatic near-ultraviolet light. Possible applications of photostimulated thermoluminescence in these crystals for ultraviolet dosimetry are discussed.