Effects induced by KrF ultraviolet excimer laser on Sn-doped silica fiber performs were analyzed by means of optical and electron paramagnetic resonance (EPR) techniques. Bond breaking in substitutional Sn sites was evidenced by the Sn-E-' EPR signal due to sp(3) unpaired electrons in threefold coordinated Sn sites. Red photoluminescence excited at 633 nm, due to nonbridging-oxygen sites, was also observed after laser exposure. The intensity of this emission did not follow the Sn concentration profile, being observed at the core-cladding interface and in the core center. Birefringence data showed that these effects are accompanied by stress relief in the Sn-doped region. Different structural features of core and cladding were evidenced by micro-Raman measurements and related to the observed photosensitivity. (C) 2000 American Institute of Physics. [S0003-6951(00)00150-9].
Chiodini, N., Ghidini, S., Paleari, A., Brambilla, G., Pruneri, V. (2000). Photoinduced processes in Sn-doped silica fiber preforms. APPLIED PHYSICS LETTERS, 77(23), 3701-3703 [10.1063/1.1330749].
Photoinduced processes in Sn-doped silica fiber preforms
CHIODINI, NORBERTO;PALEARI, ALBERTO MARIA FELICE;
2000
Abstract
Effects induced by KrF ultraviolet excimer laser on Sn-doped silica fiber performs were analyzed by means of optical and electron paramagnetic resonance (EPR) techniques. Bond breaking in substitutional Sn sites was evidenced by the Sn-E-' EPR signal due to sp(3) unpaired electrons in threefold coordinated Sn sites. Red photoluminescence excited at 633 nm, due to nonbridging-oxygen sites, was also observed after laser exposure. The intensity of this emission did not follow the Sn concentration profile, being observed at the core-cladding interface and in the core center. Birefringence data showed that these effects are accompanied by stress relief in the Sn-doped region. Different structural features of core and cladding were evidenced by micro-Raman measurements and related to the observed photosensitivity. (C) 2000 American Institute of Physics. [S0003-6951(00)00150-9].I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.