Refractive-index profiles and propagation losses of Er³⁺-doped tungsten tellurite glass waveguide by Ag⁺-Na⁺ ion-exchange

The planar waveguide of 12Na₂O·35WO₃·53TeO₂·1Er₂O₃ glass (in mol%) was prepared by Ag⁺-Na⁺ ion-exchange at 330 °C for 5 h. The effective mode indices and propagation losses of the waveguide at the wavelengths of 473, 632.8, 983.1 and 1548 nm for TE and TM modes were measured by means of a prism coupler technique. The results were compared with those of a planar waveguide of the tungsten tellurite glass without Er³⁺ ions. Especially, the propagation losses of ion-exchanged tellurite glass waveguides were estimated for the first time to the best of our knowledge.