Er3+/Yb3+ co-activated silica-alumina monolithic xerogels

Monolithic silica xerogels doped with different concentrations of Er3+,Yb3+ and Al3+ were prepared by sol-gel route. Densification was achieved by thermal treatment in air at 95°C for 120 h with a heating rate of 0.1C/min. We studied the luminescence properties of the 4I13/2®4I15/2 emission band of Er3+as a function of the Al/Er/Yb concentration and we paid particular attention to the alumina effects. Raman spectroscopy and Vis-NIR absorption were used to monitor the degree of densification of the glasses and the residual OH content.