Extrinsic- and intrinsic-defect creation in amorphousSiO2

Radiation-induced defects in fluorine-doped silica-based optical fibers: Influence of a pre-loading with H2

“…Additional measurements have been performed on the H 2 -free F-doped sample with electron spin resonance measurements (ESR) and confocal ARACOR Facility microscopy luminescence (CML) techniques [8]. These techniques provide evidence for the generation of SiE', SiODC(II) and NBOH centers that were previously associated with absorption bands around 5.7 eV (Full Width at Half Maximum = 0.68 eV); 5.03 eV (FWHM = 0.4 eV) and 4.8 eV (FWHM = 0.9 eV), respectively [9][10][11]. These three bands allow to reproduce the RIA values from 6 to 4 eV, as illustrated in Fig.…”

The E′ center and oxygen vacancies in SiO2

“…In Fig. 11, we show data by Devine [20] obtained by irradiation of wet and dry amorphous silica. Wet here means that the oxide contains more water molecules or OH groups than O 2 molecules.…”

Electron-spin-resonance identification of a -CH2·radical in irradiated amorphous SiOAustin1, Leisure2 1996Phys. Rev. B5020View full textAdd to dashboardCite

“…Previously published spectra of the 3ϫ17.5 G defect have been less than ideal for quantitative analysis due to low signal to noise ratio, 11 or interference of the above mentioned intrinsic defect signals. 8,9 In the present experiment, high signal to noise spectra were obtained by maximizing sample volume in the ESR cavity and signal averaging up to several hours. Interference of other radiation induced defects was reduced by terminating the irradiation at approximately 1 Mrad, when the 3ϫ17.5 G signal is most intense.…”

“…An intriguing problem is the electron-spin-resonance ͑ESR͒ observation of radiation induced paramagnetic centers ͑defects͒ attributed to carbon 7-10 and nitrogen 8,9,11 in Suprasil, a familiar high OH silica. 12 The puzzling aspect of these extrinsic defects in flame hydrolysis silica is that no part of the manufacturing process appears to require introduction of carbon and nitrogen.…”