6533b858fe1ef96bd12b65a1

RESEARCH PRODUCT

Spectroscopic parameters related to non bridging oxygen hole centers in amorphous-SiO2

Bruno BoizotMarco CannasLavinia Vaccaro

subject

Condensed Matter - Materials ScienceLuminescencePhotoluminescenceAbsorption spectroscopyOscillator strengthChemistrySettore FIS/01 - Fisica SperimentaleOptical spectroscopyMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesQuantum yieldSilicaCondensed Matter PhysicsAbsorptionElectronic Optical and Magnetic MaterialsMaterials ChemistryCeramics and CompositesDefectAtomic physicsAbsorption (electromagnetic radiation)SpectroscopyLuminescenceExcitation

description

The relationship between the luminescence at 1.9 eV and the absorption bands at 2.0 eV and at 4.8 eV were investigated in a wide variety of synthetic silica samples exposed to different gamma- and beta-ray irradiation doses. We found that the intensities of these optical bands are linearly correlated in agreement with the model in which they are assigned to a single defect. This finding allows to determine spectroscopic parameters related to optical transitions efficiency: the oscillator strength of the 4.8 eV results ~200 times higher than that of the 2.0 eV; the 1.9 eV luminescence quantum yield under 4.8 eV excitation is lower (by a factor ~3) than that under 2.0 eV excitation. These results are consistent with the energetic level scheme, proposed in literature for non bridging oxygen hole center, and account for the excitation/luminescence pathways occurring after UV and visible absorption

yearjournalcountryeditionlanguage
2005-03-30
http://arxiv.org/abs/cond-mat/0503699