Reaction property of diffused H2with defect Centers in GeO2-doped fiber

This paper presents the reaction property of diffused molecular hydrogen (H2) with irradiation-induced defect centers in a GeO2-doped fiber. When H2diffuses into an irradiated fiber, an OH loss increases even at room temperature. This loss increase is thought to be caused by chemical reaction between diffused H2and irradiation-induced nonbridging oxygen hole centers (NBOHC´s). The hydrogen-associated defect centers having 11.9-mT hyperfine structure are formed by chemical reaction between diffused H2and irradiation-induced Ge-defect centers. Moreover, the irradiated fiber shows an OH loss increase at high temperatures even after diffused H2is removed from the fiber. The hydrogen-associated defect centers are considered to be the hydrogen source for the OH formation.