| Autor: |
Itoh, N., Stoneham, D., Stoneham, A. M. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 11/1/2002, Vol. 92 Issue 9, p5036, 9p, 2 Diagrams, 2 Charts |
| Abstrakt: |
We suggest a model of the atomic and electronic processes responsible for the so-called 110 and 325 °C thermoluminescence (TL) peaks, including predose behavior, and for the room temperature optically stimulated luminescence (OSL) of quartz. Our model is based on defects and defect processes typical of those known from many previous studies of quartz. It explains the experimental observations that the two TL peaks and OSL are correlated with respect to the effects of thermal annealing and photoexcitation after irradiation. The model indicates that the energy for the two TL peaks and OSL is all stored by the same defect pairs. These defect pairs comprise [AlO[SUB4]][SUP-] and [X/M[SUP+]][SUP+] generated by a radiolytic reaction [AlO[SUB4]/M[SUP+]][SUP0]→ [AlO[SUB4][SUP-] + M[SUP+]. Here [AlO[SUB4]] is an Al impurity center substituting a Si atom, M[SUP+] is an alkali ion, [X/M[SUP+]] is M[SUP+] stabilized by a defect denoted by X and [AlO[SUB4]/M[SUP+]][SUP0] is an [AlO[SUB4]][SUP-] center charge compensated by M[SUP+]. Even though the 110 and 325 °C TL peaks and OSL arise from the same defect pairs, they should emit different luminescence because they arise through different mechanisms: the 325 °C TL peak through the migration of M[SUP+], and the OSL through the migration of holes. The 110 °C TL peak is ascribed to the electron-hole recombination at the [AlO[SUB4]][SUP-] centers. According to the model, the TL at 110 and 325 °C and OSL luminesce at different wavelengths. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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