Generation of efficient quasi-cw green light by single-pass frequency doubling with a periodic LiTaO3 optical superlattice

First-order quasiphase matched green light generation in a periodic LiTaO3 superlattice crystal was performed by direct frequency doubling of a quasi- continuous solid-state laser pumped by a diode. A 7.8-mum period, 14-mm lon g sample, fabricated by field poling, was used. A 38-mW, 532-nm green light output was obtained from the sample with an incidence power of 256 mW near room temperature, which corresponds to 15% single-pass conversion efficien cy. No obvious photo-refractive damage was observed in the operation temper ature and power level. The measured effective nonlinear coefficient is 7 pm /V. The measured temperature band width of 3 degreesC corresponds to the th eoretical value. (C) 2000 Elsevier Science B.V. All rights reserved.