Ridge waveguides in lithium niobate fabricated by differential etching following spatially selective domain inversion

Ridge structures have been fabricated in z-cut LiNbO3 using the technique of differential etching following spatially selective domain inversion. Waveguides within these ridges have been achieved using the techniques of ion beam implantation, proton exchange, and titanium indiffusion. Using this last method, guides with losses <0.8dB/cm have been realised for light at a wavelength of 1.3µm. We briefly discuss applications for these structures.