Structural engineering of germanosilicate glass network for enhanced Bi: NIR luminescence

Abstract Bi can experience chemical-state evolution by structural engineering of glass network, which is favorable for the efficient manipulation of final luminous property, as well as the extensive potential in new type fiber lasers and optical amplifiers. In this work, the typical structure of glass is transformed and optimized by designing and tuning both the glass network formers and modifiers. It is fist time to demonstrate that the mixed-structure effect produced by the formation of the hybrid structure (SiO2-GeO2) is conducive to the Bi-related near-infrared (NIR) emission. In addition, the dispersion of Bi-related NIR emission centers is further tailored by the AlO5 hexahedra in this multicomponent glass, which is claimed by both NMR and emission spectra. Furthermore, a suitable reduction atmosphere is designed appropriately to promote the NIR luminescence to a larger extent. This work is expected to be helpful for improving the performance of existing Bi-doped glass and fibers. Our results indicate that the tuned multicomponent germanosilicate glasses with mixed structure and optimal reduction effect can be promising material as high performance photonic glasses.