High temperature ESR study of Fe(III) in various vitreous matrices

The Raman spectra of binary high-silica glasses have been studied. The main peaks at 808 cm^?1 and 710 cm^?1 in vitreous B₂O₃ and vitreous P₂O₅, respectively, are greatly reduced in binary high-silica glass, whereas a peak at 425 cm^?1 due to GeOGe vibration and a peak at 1320 cm^?1 due to P = O vibration remain strong, increasing in intensity with decreasing SiO₂ concentration. In the stimulated Raman spectra of a P₂O₅-SiO₂ glass fiber pumped by a mode-locked and Q-switched Nd:YAG laser at 1.064 μm, strong Stokes emissions due to the P = O vibration have been observed at 1.24 μm and 1.48 μm. In the spectra for a GeO₂-SiO₂ glass fiber, four narrow-width Stokes emissions due to the GeOGe vibration have been observed at 1.115, 1.172, 1.235 and 1.305 μm.