Optical properties of Ge-oxygen deficient centers embedded in silica films
- Autori: Messina, F.; Agnello, S.; Boscaino, R.; Cannas, M.; Grandi, S.; Quartarone, E.
- Anno di pubblicazione: 2007
- Tipologia: Articolo in rivista (Articolo in rivista)
- OA Link: http://hdl.handle.net/10447/17542
The emission features of Ge-oxygen deficient centers in a 100 nm thick Ge-doped silica films were investigated by looking at the photoluminescence spectra and time decay under synchrotron radiation excitation in the 10–300 K temperature range. These centers exhibit two luminescence bands centered at 4.3 eV and 3.2 eV associated with the de-excitation from singlet (S1) and triplet (T1) states, respectively, that are linked by an intersystem crossing process. The comparison with results obtained in a bulk Ge-doped silica sample shows that the efficiency of the intersystem crossing process depends on the properties of the matrix embedding the Ge-oxygen deficient centers, being more effective in the film than in the bulk counterpart.