Effect of adding TiO2 as modifier on the optical thermometric ability of tellurium tungstate glass

Abstract

This work investigates the effect of incorporating TiO2 on the optical properties of the Er3+/Yb3+ doped/codoped tungstate-based tellurite (TW) glasses. The optical bandgap and Urbach energy analysis indicates that the structure of the binary tungstate glass gets modified due to the incorporation of TiO2. The Judd-Ofelt analysis shows that the bonding between the activator and ligand oxygen ions is ionic in nature and the ionicity of the bond increases with the TiO2 content. The incorporation of TiO2 enhances the green and red UC emission intensity of the Er3+ doped TW (TW_0.6) glass by ∼ 39 and ∼ 140 times respectively. The relative sensitivity of the Er3+/Yb3+: TW glass having 10 mol% of TiO2 is found to be as high as ∼ 0.01236 K−1 at 300 K.