Fluoride glass planar optical waveguides by anionic exchange

The feasibility of graded-index waveguiding structures by anion-exchange on glass substrates has been shown for the first time to our knowledge. A new technology has been developed to produce integrated optical components on fluoride glass substrates by anionic exchange from either water or heavy water vapor-containing gas flows.D2O-made waveguides operating from UV up to 1.8 mu m, and from 2.55 to 3.6 mu m, have been proved to be easily achievable. The refractive index profile of one planar waveguide has been determined, revealing 10 guided modes at 0.633 mu m, which is widely better than the best results previously obtained by cation-exchange.