TYPE-II 2ND-HARMONIC GENERATION AND SUM-FREQUENCY MIXING IN UNIFORM KTIOPO4 CHANNEL WAVE-GUIDES

Type-II second-harmonic generation was investigated in channel wavegui des fabricated in potassium titanyl phosphate (KTiOPO4) crystals by io n exchange. The birefringence of the guided-wave structure was used to provide phasematching. A green (509 nm) output power of 0.25 mW was p roduced by frequency doubling the 1018-nm output of a titanium:sapphir e laser; this power is 200 times greater than what would be obtained i n the corresponding bulk interaction. Phasematching for second-harmoni c generation was found to have broad tolerances with respect to temper ature and wavelength. Blue light at 483 nm was produced by sum-frequen cy mixing of 1064-nm and 883-nm light.