Ag ⁺ -Na ⁺ exchanged waveguides frommolten salts in a chemically durable phosphate glass

The authors report that Ag+-Na+ ion exchange has been performed for the first time from molten salt baths in a chemically durable phosphate glass. Characterisation of planar waveguides, fabricated at different temperatures, diffusion times and with varying melt concentrations, indicates large diffusion coefficients and higher index changes with no deterioration of surface quality.