On the possibility of photo- and photo-thermal depletion of deep traps in α-Al2O3-δ

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Beam interactions with materials and atoms, 2020-03, Vol.467, p.97-101
• Main Authors: Surdo, A., Abashev, R., Milman, I.
• Format: Article
• Language: English
• Subjects: Anion-deficient corundum; Deep traps; High-temperature thermoluminescence; Photo- and photo-thermal depletion
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2020.02.004

In this study, we explored the possibility of photo- and photo-thermal depletion of deep traps in anion-deficient corundum (α-Al2O3-δ) crystals and luminescent storage dosimeters on their basis. As a result of repeated normal use or a single exposure to high-dose radiation, these traps become filled, which reduces significantly the informative response of thermally and optically stimulated luminescence (TL and OSL) due to the depletion of the main dosimetric trap. It has been found that effective photodepletion of the deep trap causing the 830 K TL peak, whose filling affects the informative TL and OSL responses most of all, is only possible in α-Al2O3-δ crystals and unpacked TLD-500 detectors on their basis. In the majority of cases, including practically important ones associated with the restoration of the dosimetric properties of widely employed α-Al2O3-δ dosimeters, photothermal depletion proves to be more effective.