Tensile strain induced changes in the optical spectra of SrTiO.sub.3./sub. epitaxial thin films

0349835 - FZÚ 2011 RIV RU eng J - Journal Article
Dejneka, Alexandr - Tyunina, M. - Narkilahti, J. - Levoska, J. - Chvostová, Dagmar - Jastrabík, Lubomír - Trepakov, Vladimír
Tensile strain induced changes in the optical spectra of SrTiO₃ epitaxial thin films.
Physics of the Solid State. Roč. 52, č. 10 (2010), 2082-2089. ISSN 1063-7834. E-ISSN 1090-6460
R&D Projects: GA ČR GA202/08/1009; GA AV ČR KAN301370701; GA MŠMT(CZ) 1M06002
Institutional research plan: CEZ:AV0Z10100522
Keywords : SrTiO₃ epitaxial thin films * effect of biaxial tensile strains on optical spectra
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 0.727, year: 2010

Effect of biaxial tensile strains on optical function and band edge transitions of ultra thin epitaxial films was studied using as an example a 13 nm thick SrTiO3 films deposited on KTaO3 (100) single crystal substrates. Optical functions in the 200–1200 nm spectral range were determined by spectroscopic ellipsometry technique. It was found that tensile strains result in a shift of the low energy band gap optical transitions to higher energies and decrease the refractive index in the visible region. The observed effect is connected with changes in the lowest conduction and in the top valence bands that are due to increase of the in-plane lattice constant and/or onset of the polar phase in the tensile-strain induced ultra-thin SrTiO3 films.
Permanent Link: http://hdl.handle.net/11104/0006115