Effect of hydrogen loading and UV irradiation on the gain of Er$^{3+}$-doped fibers

Abstract

Molecular hydrogen loading and a subsequent 193-nm ultraviolet (UV) irradiation influence on the gain properties of Er3+-doped core silica optical fibers are demonstrated in this work. The dynamics of photoinduced changes’ formation and subsequent dissociation in this fiber type is demonstrated. H2 loading results in less than a 10% fiber-gain decrease, whereas subsequent UV irradiation results in almost twice the gain degradation. Furthermore, UV-induced defects partially dissociate under the influence of 976-nm pump radiation. At least two independent types of gain degradation mechanisms of H2-loaded active fiber under the influence of UV irradiation are shown.