Quasi-phase-matched (QPM) UV second-harmonic generation (SHG) in a periodically poled MgO:LiNbO<sub>3</sub> waveguide is presented. A ridge-type waveguide with high nonlinearity and strong resistance to photorefractive damage was achieved by use of an ultraprecision machining technique. By use of this waveguide in 1.4-μm periodically poled MgO:LiNbO<sub>3</sub> , a first-order QPM SHG device for 340-nm UV radiation was demonstrated. In a single-pass configuration, continuous-wave 22.4-mW UV light was generated for a fundamental power of 81 mW, corresponding to a normalized conversion efficiency of 340%/W.
© 2003 Optical Society of America
Kiminori Mizuuchi, Tomoya Sugita, Kazuhisa Yamamoto, Tatsuo Kawaguchi, Takeshi Yoshino, and Minoru Imaeda, "Efficient 340-nm light generation by a ridge-type waveguide in a first-order periodically poled MgO:LiNbO3," Opt. Lett. 28, 1344-1346 (2003)