Fabrication of periodically domain-inverted channel waveguides in lithium niobate for second harmonic generation

A method to produce periodically domain-inverted channel waveguides in LiNbO/sub 3/ is reported. With this type of waveguide, using quasi-phase matching (QPM), arbitrary wavelengths can be frequency doubled by choosing the appropriate period. It is concluded that, with improved fabrication methods, it will be possible to generate milliwatts of blue light with a diode laser as pump, which is of considerable interest.>