A study of the photorefractive effect in linbo3: Ti waveguides by using pulsed illumination at 810 nm

There is increasing interest in LiNbO3:Ti integrated optical devices as transducers in fast, analog, data-acquisition systems. A possible limitation to such use, however, results from the photorefractive effect in LiNbO3:Ti. From existing data, we know of difficulties due to the photorefractive effect with continuous-wave (CW) illumination. Here we present pulse measurements at 810 nm of the optical-transmission distortion due to the photorefractive effect in LiNbO3:Ti waveguides. We subjected the optical devices to pulsed input light generated by a mechanically shuttered dye-laser system. We then measured and compared the transmitted light to an input monitor and obtained the transmission of the LiNbO3:Ti devices as a function of time. We varied the peak power from 50 pW to 150 mW, and the pulse length from 10 ms to 1 s. We have obtained a 21-mW output with a 10-ms duration from a LiNbO3:Ti waveguide with no prom2t transmission degradation. Further, we have found preliminary evidence suggesting an activation time of 100 to 150 min. for the onset of photorefractive transmission degradation.