Effect of B2O3 on the fluorescence of Er-doped Ge–B–P–SiO2 glasses for waveguide amplifier

Abstract Er3+-doped silica glasses were prepared with similar composition to the waveguide core film of silica planar lightwave circuit (PLC) and tested for the basic photoluminescence characteristics to investigate the influence of B-doping. In the material viewpoint, the major difference between conventional fiber amplifier and waveguide amplifier is the chemical composition of host glass, especially B2O3. Er-doped silica bulk glasses were prepared with various B2O3 concentrations by melt and quenching method and waveguide films were prepared by flame hydrolysis deposition. Fluorescence spectra were measured for both type of specimen to clarify the effect of B2O3 and form of Er on basic amplification characteristics. According to the results of the fluorescence measurements, we could confirm the depression of the concentration quenching of Er ions by the doping of B2O3 and this is believed to be due to the formation of 4-coordinated boron in silica network.