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 o f differential etching following spatially selective domain inversion. Wave guides within these ridges have been achieved using the techniques of ion b eam implantation, proton exchange, and titanium indiffusion. Using this las t method, guides with losses <0.8 dB cm(-1) have been realized for light at a wavelength of 1.3 mu m. We briefly discuss applications for these struct ures. (C) 1999 American Institute of Physics. [S0003-6951(99)00810-4].