Ferroelectric-domain inversion induced by SiO ₂ cladding for LiNbO ₃ waveguide SHG

Abstract

It was found that, by heating an LiNbO3 crystal with SiO2 cladding on the + z face, ferroelectric-domain inversion is induced under the cladding. The inversion method offers high reproducibility and is suitable for fabrication of quasiphase-matching waveguide SHG devices. A prototype device was fabricated and SHG was demonstrated using a CW-YAG laser.