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H(II) centers in natural silica under repeated UV laser irradiations

F. Messina·M. Cannas·R. Boscaino
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Abstract

We investigated the kinetics of H(II) centers (=Ge'-H) in natural silica under repeated 266nm UV irradiations performed by a Nd:YAG pulsed laser. UV photons temporarily destroy these paramagnetic defects, their reduction being complete within 250 pulses. After re-irradiation, H(II) centers grow again, and the observed recovery kinetics depends on the irradiation dose; multiple 2000 pulses re-irradiations induce the same post-irradiation kinetics of H(II) centers after each exposure cycle. The analysis of these effects allows us to achieve a deeper understanding of the dynamics of the centers during and after laser irradiation.

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F. Messina, M. Cannas, R. Boscaino. 2004-10-22. H(II) centers in natural silica under repeated UV laser irradiations. https://doi.org/10.1016/j.jnoncrysol.2005.04.012

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