0-dB wavelength conversion using direct-bonded QPM-Zn : LiNbO3 ridge waveguide

We fabricate a 50-mm-long ZnO-doped quasi-phase matched LiNbO
₃
ridge waveguide by employing the direct bonding method. A second-harmonic generation conversion efficiency of 560%/W and an output power of 110 mW with a pump power of 190 mW are achieved. We demonstrate 1.55-μm band wavelength conversion based on a /spl chi//sup (2)/ cascade scheme. An internal wavelength conversion efficiency of -0.3 dB is successfully achieved.