Planar Optical Waveguides in KNbO₃ Formed by MeV B and He Ion Implantation

Planar optical waveguides in single crystals of KNbO₃ were fabricated by MeV B and He ion implantation. The depth profiles of radiation damage in these waveguides were compared and analyzed by high resolution transmission electron microscope. Non leaky waveguiding modes (TE₀ and TM₀), which are due to implantation induced increase of nb and n_c, were observed in 6.0 MeV B ion implantated waveguides with a dose of 1 x 10¹⁵cm^-2.