Radial distribution of some defect-related optical absorption and PL bands in silica glasses

In order to investigate the origins of defect-related optical absorption and photoluminescence (PL) bands in silica glasses, we measured the radial distribution of paramagnetic defect centers, optical absorption band, and PL band in various silica glass rods. We studied the radial distribution of the following: the E′ center and the 5.8 eV absorption band, non-bridging oxygen hole center and the 1.9 eV PL band and 4.8 eV absorption band, and 5.0 eV absorption band and the 2.7 and 4.3 eV PL bands. As a result of this study, we confirmed the correlation of both the radial distributions. These results suggest the following: the E′ center is the origin of the 5.8 eV absorption band, the non-bridging oxygen hole center is the origin of the 1.9 eV PL band and 4.8 eV absorption band, and the oxygen vacancy is the origin of the 5.0 eV absorption band, the 2.7 and 4.3 eV PL bands.