Structural and optical properties of epitaxial BaTiO3 thin films grown on GdScO3(110)

We have prepared 1-mum-thick epitaxial BaTiO3 thin films on GdScO3(110) using pulsed laser deposition. The structural perfection of the films was revealed by a rocking curve width of Deltaomega=0.13degrees for the 002 BaTiO3 reflection and a Rutherford backscattering spectrometry/channeling minimum yield, chi(min), of 0.5% measured for the Ba signal behind the surface peak. High-resolution transmission electron microscopy revealed an epitaxial relationship between BaTiO3 and GdScO3 and a sharp interface between the substrate and the film. The refractive index of the BaTiO3 film was n(o)=2.329+/-0.002 and n(e)=2.307+/-0.002 at a wavelength of 632.8 nm and n(o)=2.248+/-0.002 and n(e)=2.228+/-0.002 at a wavelength of 1523 nm. The optical losses were less than 2 dB/cm at a wavelength of 632.8 nm. (C) 2003 American Institute of Physics.