Optical Properties and Photosensitivity of Vacuum Synthesized Ge-doped Sol-Gel Amorphous SiO2

We report optical and electron paramagnetic resonance investigations of gamma ray irradiation effects in solgel Ge-doped amorphous SiO2. The studied materials have Gedoping levels up to 104 molar part per million and were densified by two routes differing for the atmosphere: O 2+N2 or vacuum. The obtained results evidence that irradiation affects matrix sites inducing paramagnetic defects. Furthermore, the comparison between the two densification procedures shows that vacuum atmosphere induces higher radiation sensitivity.