Effect of annealing on photorefractive damage in titanium-indiffused LiNbO/sub 3/ modulators

Abstract
We have evaluated photorefractive effects at 1320-nm and 1064-nm optical wavelengths in interferometric modulators built using Ti-indiffused waveguides in lithium niobate. The sensitivity to photorefractive damage is substantially increased by anneals in non-oxygen atmospheres at temperatures /spl ges/200/spl deg/C. The sensitivity can be reduced by an anneal in oxygen. Properly annealed modulators operated for 150 h with 400 mW at 1320 nm with no photorefractive effects other than a 3/spl deg/ change in bias point.