Temperature dependence of the optical propertiesof Ba.sub.0.75./sub.Sr.sub.0.25./sub.TiO.sub.3./sub. thin films

0439394 - FZÚ 2015 RIV CH eng J - Journal Article
Železný, Vladimír - Chvostová, Dagmar - Pajasová, Libuše - Jelínek, Miroslav - Kocourek, Tomáš - Daniš, S. - Valvoda, V.
Temperature dependence of the optical propertiesof Ba_0.75Sr_0.25TiO₃ thin films.
Thin Solid Films. Roč. 571, č. 3 (2014), s. 416-419. ISSN 0040-6090. E-ISSN 1879-2731.
[International Conference on Spectroscopic Ellipsometry /6./. Kyoto, 26.05.2013-31.05.2013]
Institutional support: RVO:68378271
Keywords : thin films * optical properties * perovskites * ellipsometry
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 1.759, year: 2014

Optical properties of Ba0.75Sr0.25TiO3 (BST(75/25)) ferroelectric thin film have been investigated by spectroscopic ellipsometry in a broad temperature interval from 10 to 300 K. The polycrystalline perovskite-phase BST films were prepared by pulsed laser deposition technique. The complex dielectric functions and optical parameters of the films were determined in the 1.5–5.5 eV spectral range. The spectra can be divided into two distinctive regions according to themagnitude of absorption coefficient separated by a band gap. An apparent reduction of the band gapwas observed on increasing temperature. This can be ascribed to the renormalization of electronic band structure due to the electron–phonon interaction, which follows the Bose–Einstein model.
Permanent Link: http://hdl.handle.net/11104/0242684