Electro-optically switched coupler with stepped Δβ reversal using Ti-diffused LiNbO3 waveguides

An experimental electro-optical switched directional coupler is reported which is formed in LiNbO3 by diffused Ti strip waveguides and uses stepped reversed phase mismatching to provide electrical adjustment of both switch states. A measured 400:1 conversion of light from one guide to the other was obtained.