High-index overlay gratings on K/sup +/-exchanged waveguides in BK-7 glass using excimer laser ablation

Summary form only given.Bragg relief gratings overlaid on optical waveguides may be used as high-extinction ratio wavelength filters with applications in integrated optics and optical communications. Bragg gratings have been written using electron beam lithography and etching on a complex waveguide structure consisting of a thin silicon overlay on ion diffused waveguides in LiNbO/sub 3/. This configuration enhances the guided field closer to the surface resulting in strong interaction with the film region. A new waveguide grating design process which relies on a novel grating patterning method and new materials will be presented in this paper. This design consists of the combination of a potassium ion-exchanged single-mode channel waveguide with a high index film (InO/sub x/) overlaid on its upper surface.