EPITAXIAL FERROELECTRIC THIN-FILMS PREPARED BY THE SOL-GEL TECHNIQUE

The sol-gel process was used to fabricate epitaxial thin films of crys talline ferroelectric oxides, including KNbO3 film on single crystal s ubstrates of MgO and SrTiO3, LiNbO3 film on LiTaO3 and alternatively m ultilayer nX(SrTiO3/PbTiO3) Films on SrTiO3. Fabrication of these epit axial thin films will be described. The structure of these films has b een studied with X-ray, electron diffraction, and high resolution elec tron microscopy. Second harmonic generation of 1064 nm incident light was demonstrated in KNbO3 waveguides. Transient photorefractive gratin gs in Fe-doped KNbO3 were studied by a two-beam coupling technique at various writing intensity and wavelength.