Wavelength Conversion of an Infrared Signal Through Cascaded Second-Order Nonlinearity in a Lithium-Niobate Channel Waveguide

Abstract

We describe a wavelength conversion experiment (generation of a pulse at the wavelength λp − ∆λ from a signal at λp + ∆λ under the action of a pump at λp) performed through a cascaded second-order process in a lithium niobate channel waveguide. With a 58-mmlong Ti diffused channel waveguide, λp = 1.1 µm (the wavelength of phase matching for the first step of sh generation), ∆λ of several nanometers and 20 ps pulse duration, wavelength conversion with unit efficiency is obtained with a pump pulse energy of the order of 10 2 pJ. The experimental results are successfully interpreted by making use of modal analysis and solving the appropriate nonlinear equations.