Abstract
A planar waveguide was formed in fused silica plate by implantation of 5-MeV Ge2+ ions to a dose of 1015 ions cm2. Thermal poling created larger second-order nonlinearity in the waveguide than in blank fused silica plate. The nonlinearity could be erased by 266 nm ultraviolet exposure. Periodical nonlinearity distribution in the waveguide was implemented by periodical UV exposure. The first-order quasi-phase-matched second-harmonic generation from 1064 nm fundamental mode to 532 nm fundamental mode was achieved in the waveguide. The d33: d31 ratio was found to be 3.2:1, in favor of the built-in electric field model for Ge -implanted silica waveguide. © 2005 American Institute of Physics.