Optical waveguide device and second harmonic generator using the same

摘要

An optical waveguide device for use as a second harmonic generator includes a nonlinear optical crystalline substrate of KTiOPO4 and an optical waveguide core of a dielectric material, such as Ta2O5, disposed on the nonlinear optical crystalline substrate. The optical waveguide converts a fundamental wave having a wavelength lambda which is guided through the optical waveguide into a second harmonic wave having a wavelength lambda /2, the second harmonic wave having the same polarization as the fundamental wave which is guided through the optical waveguide. The optical waveguide has a thickness of 190 nm or greater. The optical waveguide device also has a dielectric loaded strip disposed on the optical waveguide core. The dielectric loaded strip may be made of SiO2 or SiO2 doped with Ta2O5. Alternatively, the optical waveguide may be a ridge-type optical waveguide, and the optical waveguide device may also has a cladding layer disposed on the nonlinear optical crystalline substrate and the optical waveguide core.