42-PERCENT-EFFICIENT SINGLE-PASS CW 2ND-HARMONIC GENERATION IN PERIODICALLY POLED LITHIUM-NIOBATE

We present a full-wafer fabrication process for periodically poled lit hium niobate with a 6.5-mu m domain period. Samples that were 53 mm lo ng and 0.5 mm thick were obtained with this process for single-pass cw 1064-nm Nd:YAG second-harmonic generation. These samples exhibited 78 % of the ideal nonlinear coefficient, had a measured conversion effici ency of 8.5%/W in the low-power limit, and produced 2.7 W of cw 532-nm output with 6.5 W of cw input, which corresponds to 42% power convers ion efficiency. (C) 1997 Optical Society of America.