6533b7cffe1ef96bd1257d29
RESEARCH PRODUCT
Isoelectronic series of oxygen deficient centers in silica: experimental estimation of homogeneous and inhomogeneous spectral widths
Fabrizio MessinaMarco CannasMaurizio LeoneRoberto BoscainoMichele D'amicosubject
PhotoluminescenceMaterials scienceOscillator strengthTemperatureFOS: Physical sciencesSilicaElectronsDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural NetworksNanosecondSilicon DioxideMolecular physicsCrystallographic defectOxygen Deficient CenterOxygenLaser linewidthMolecular vibrationAtomLuminescent MeasurementsInhomogeneous Spectral WidthPhysical and Theoretical ChemistryExcitationdescription
We report nanosecond time-resolved photoluminescence measurements on the isoelectronic series of oxygen deficient centers in amorphous silica related to silicon, germanium and tin atoms, which are responsible of fluorescence activities at approximately 4 eV under excitation at approximately 5 eV. The dependence of the first moment of their emission band on time and that of the radiative decay lifetime on emission energy are analyzed within a theoretical model able to describe the effects introduced by disorder on the optical properties of the defects. We obtain separate estimates of the homogeneous and inhomogeneous contributions to the measured emission line width, and we derive homogeneous spectroscopic features of the investigated point defects (Huang-Rhys factor, homogeneous width, oscillator strength, vibrational frequency). The results point to a picture in which an oxygen deficient center localized on a heavier atom features a higher degree of inhomogeneity due to stronger local distortion of the surrounding matrix. For Si, Ge, and Sn related defects, the parameter lambda, able to quantify inhomogeneity, is 65, 78, and 90%, respectively.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-01-01 |