Difference frequency mixing in LiNbO/sub 3/ waveguides using an adiabatically tapered periodically-segmented coupling region

Summary form only given. We optimized waveguide designs for mixing 755-785 nm with 1064 nm to generate 2.6-3.0 /spl mu/m based on previously developed models of the linear and nonlinear properties of annealed proton exchanged (APE) LiNbO/sub 3/ waveguides. To solve the mode-coupling problem we developed a hybrid waveguide structure. The input region is single moded at both near-IR input wavelengths, the connecting segment is adiabatically tapered to effect mode conversion to the fundamental mode of the difference frequency generation (DFG) waveguide, and the mixing region is optimized for DFG of the idler wavelength.