Infrared reflection spectroscopy and optical constants of LiNbO3 films on crystal substrates

We have measured infrared reflectivity spectra of thin lithium niobate films of nanometer thickness, grown by a pulsed laser deposition technique using KrF-excimer laser (λ=248 nm) on the single crystalline substrates (sapphire, MgO, NdGaO3 and SrTiO3). Using the dispersion analysis technique, we have calculated thicknesses and optical constants of the films. The phonon parameters of the substrates and films are obtained.