Temperature dependence of the generation and decay of E' centers induced in silica by 4.7 eV laser radiation
- Autori: Messina, F.; Cannas, M.
- Anno di pubblicazione: 2009
- Tipologia: Articolo in rivista (Articolo in rivista)
- Parole Chiave: Silica, laser effects, annealing
- OA Link: http://hdl.handle.net/10447/38882
We report a study of the generation of silicon dangling bonds (E' centers) induced in fused silica by 4.7 eV laser irradiation in the 10 < T < 475 K temperature range, carried out by in situ optical absorption spectroscopy. The generation of the defects. occurring by transformation of pre-existing precursors, results to be a thermally activated process, quenched below 150 K and with a 0.044 eV activation energy. At T > 200 K the induced defects undergo a post-irradiation decay due to their reaction with mobile H(2). The interplay between generation and annealing gives rise to a bell-shaped temperature dependence of the concentration of induced E' centers, peaking at 250 K