Abstract
Abstract The absorption band peaking at 5.17 eV, which is due to neutral oxygen deficient vacancy, in rf-sputter deposited GeO2-SiO2 thin glass films was bleached by ultraviolet-illumination, and an intense absorption band was induced around 6.4 eV. The refractive index change calculated via Kramers-Kronig relations was of the order of 10−4, which was higher by one order of magnitude than those of bulk germanosilicate glasses prepared by VAD method. The concentration of Ge E’ centers increased with the intensity of the 6.4 eV band. The oscillator strength of the 6.4 eV band, however, exceeded unity on the assumption that Ge E’ centers exclusively induce this band. It was, therefore, concluded that not only Ge E’ center but also other photochemically induced color centers give the 6.4 eV band, which is the origin of large refractive index change.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
