Spectroscopy of an optical excited Ga doped SiO_2 surface

摘要

We present the first spectroscopical analysis of the Ga/SiO_2 surface interaction in hot environment.This interaction gives rise to inclusions of Ga atoms inside the silica matrix that produce structural changes and modify the SiO_2 optical characteristics.This paper discusses both the time-and the frequency-resolved spectra of the fluorescence emission following UV pulsed laser excitation of the so "doped"silica in the range 15,000-28,000 cm~(-1).The investigation is completed by the electron paramagnetic resonance (EPR)spectra of two high-purity synthetic silica samples of commercial origin after thermal treatment in presence and in absence of a Ga atmosphere.