Abstract
We investigated the red-luminescence band at 1.9 eV in a gamma ray irradiated synthetic wet silica, under ultraviolet and vacuum-ultraviolet excitations in the temperature range 17–300 K. The excitation profile detected at T517 K evidences a broad band peaked at 6.4 eV, with full width at half maximum of 1.7 eV, besidesthe well-known component at 4.8 eV. On increasing the temperature up to T5300 K, for both ultraviolet and vacuum-ultraviolet excitations, the red luminescence decreases by a factor 10. These results give experimentalsupport to the assignment of the vacuum-ultraviolet absorption transition to a nonbridging oxygen hole center,proposed in a recent paper (T. Suzuki et al., Phys. Rev. Lett. 90, 186404, 2003). Moreover, the thermal quenching of the red-luminescence evidences the activation of a nonradiative relaxation channel inhibiting theradiative emission from the excited state.
Lingua originale | English |
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pagine (da-a) | 153201-1-153201-3 |
Rivista | PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS |
Volume | 69 |
Stato di pubblicazione | Published - 2004 |
All Science Journal Classification (ASJC) codes
- ???subjectarea.asjc.2500.2504???
- ???subjectarea.asjc.3100.3104???