Fiber drawing ability and loss optimization of niobium rich borophosphate optical glass fibers

Here we explore the manufacturing of niobium-rich borophosphate glasses into fibers with optical quality. Glass preforms composition [(100-x) (0.95 NaPO3 + 0.05 Na2B4O7) - x Nb2O5] = 37, 38, 39, 40 were synthetized and thermally drawn. Viscosity measurements performed in softening point range show that fiber drawing temperature gradually increases amount niobium oxide. X-ray diffraction Raman structural analysis post demonstrate BPN glass 39% Nb2O5 represents upper limit for under oxygen. Subsequently, preform quenching protocol was optimized to mitigate density fluctuations within matrix related convection flows compare conventional cast-in-mold method. Optical transmission shadowscopy imaging highlight improvement quality produced following this new protocol. This observation is confirmed by cut back loss which a decreasing attenuation from 6.04 dB/m 3.19 between two methods. One believes rich improved highlights their potential be used as near-infrared highly nonlinear waveguide devices.