Epitaxial growth of potassium lithium niobate single-crystal films for optical-waveguides

K3Li2Nb5O15 (KLN) single crystal films have been successfully grown with good epitaxy onto K2BiNb5O15 substrates by EGM, LPE and rf-sputtering methods, and onto sapphire substrates by rf-sputtering. Evaluation of these. KLN films by X-ray and reflection electron diffraction measurements and results on optical waveguide are reported. The ordinary refractive index of the film was no=2.27. The TE0 mode optical propagation loss in an about 2. 7μm-thick KLN film, sputtered on a sapphire substrate, was 7.8dB/cm at 6328Å.