Extended Short-wavelength Harmonic Production Using a Multilayer Waveguide Structure

Abstract
A composite optical waveguide structure is proposed which is calculated firstly to extend the operating range of second-harmonic generation to shorter wavelengths, and secondly to improve its conversion efficiency. In an example using LiNbO3 it is shown that second-harmonic output is feasible down to 435 nm and the overall efficiency is doubled relative to mode matching in a simple waveguide structure.