Effects of La3+ and Y3+ doping on spatial homogeneity of Ho3+ ions in high silica glass

Abstract In this work, we have investigated the influence of La3+ and Y3+ doping on the spatial homogeneity of Ho3+ ions in high silica glasses via structural and spectroscopic analyses. It is found that both of La3+ and Y3+ doping could lead to depolymerization of the glass network. Under the same doping concentration, Y3+ gives rise to a larger silicate connectivity than La3+. The spinning sideband patterns of the 27Al NMR spectra indicate that the population of Ho3+ ions in the vicinity of Al3+ decreases with the increase in the concentration of La3+ or Y3+. In comparison to La3+, the doping of Y3+ more favors Ho3+ ions to be populated around Al3+ in the glass network. The fluorescence centered at ~2 μm from Ho3+ ions exhibits an increase tendency when increasing the concentration of La3+ or Y3+. The results indicate that the doping of La3+ or Y3+ ions into high silica glasses can improve the spatial distribution homogeneity of Ho3+ ions and La3+ plays a more positive role than Y3+.