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Optical properties of Ge-oxygen defect center embedded in silica films

F. Messina·S. Agnello·R. Boscaino·M. Cannas·S. Grandi·E. Quartarone
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Abstract

The photo-luminescence features of Ge-oxygen defect centers in a 100nm thick Ge-doped silica film on a pure silica substrate were investigated by looking at the emission spectra and time decay detected under synchrotron radiation excitation in the 10-300 K temperature range. This center exhibits two luminescence bands centered at 4.3eV and 3.2eV associated with its de-excitation from singlet (S1) and triplet (T1) states, respectively, that are linked by an intersystem crossing process. The comparison with results obtained from a bulk Ge-doped silica sample evidences that the efficiency of the intersystem crossing rate depends on the properties of the matrix embedding the Ge-oxygen defect centers, being more effective in the film than in the bulk counterpart.

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F. Messina, S. Agnello, R. Boscaino, M. Cannas, S. Grandi, E. Quartarone. 2007-03-02. Optical properties of Ge-oxygen defect center embedded in silica films. https://doi.org/10.1016/j.jnoncrysol.2006.10.033

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