Luminescence of Ti3+ ions in silica glass

The d – d luminescence of Ti³⁺ ions was first observed in the double Ti/SiO₂ system at room temperature. Silica glass doped with titanium was synthesised in a steady- state laser plume. The luminescent state was obtained by producing oxygen-deficient centres in the chemical reaction between Ti and SiO₂. Comparison of the luminescence and absorption spectra of the titanium-doped silica glass with the spectra of a Ti³⁺:Al₂O₃ crystal suggests that the 690-nm luminescence band belongs to Ti³⁺ ions.