Precise regulation of Bismuth Active Centres in alkaline earth ions-doped Ga2O3-GeO2 glasses by Bi-Al pre-combination

Abstract

、Bismuth (Bi)-doped glasses and optical fibers have been widely applied in the research of tunable lasers and amplifiers due to their ultra-broadband near-infrared (NIR) luminescence, which originates from the Bismuth active centres (BACs). Traditional methods for regulating BACs typically involve pre-treatment strategies, such as altering glass composition and adjusting the structure units of glass, as well as post-treatment methods, including thermal activation. However, these approaches struggle to precisely regulate the surrounding environment of the BACs, as they mainly depend on structure changes in glass network induced by network modifiers or post-treatments. In this study, we break through traditional methods and propose a strategy for the precise regulation of BACs by Bi-Al pre-combining in the form of Bi2(Al2O4)3 doping. The effectiveness of this strategy is furthered validated by modifying the alkaline earth ions species. The results demonstrate that this method significantly raises the Bi concentration quenching threshold, helping to overcome the limitations of low BACs concentrations in Bi-doped fibers. Furthermore, it improves the photostability of BACs under continuous 830 nm pumping and reduces the differences in photostability across different alkaline earth ion glasses, thus facilitating further application research on Bi-doped optical amplifiers.