Infrared spectroscopy of an epitaxial BaTiO.sub.3./sub./SrTiO.sub.3./sub. superlattice grown on a (110) SmScO.sub.3./sub. substrate

0440728 - FZÚ 2015 RIV US eng J - Journal Article
Železný, Vladimír - Soukiassian, A. - Schlom, D. G. - Xi, X.X.
Infrared spectroscopy of an epitaxial BaTiO₃/SrTiO₃ superlattice grown on a (110) SmScO₃ substrate.
Journal of Applied Physics. Roč. 115, č. 18 (2014), "184102-1"-"184102-7". ISSN 0021-8979. E-ISSN 1089-7550
R&D Projects: GA ČR(CZ) GAP204/11/1011
Institutional support: RVO:68378271
Keywords : perovskites * superlattices
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 2.183, year: 2014

Polarized infrared reflectance spectra of a BaTiO3/SrTiO3 superlattice deposited on the (110) cut of SmScO3 substrate and bare substrate have been studied in the broad temperature range from 10 to 650 K. Strong infrared anisotropy of the SmScO3 substrate was observed and explained as a projection of B 1 u and B 2 u  + B 3 u phonons into the (110) plane. In the polarization parallel to the c-axis below 200 cm−1, an anomaly in the temperature dependence of the spectra was observed. Fitting the superlattice and substrate spectra, the parameters of optical phonons and their temperature dependence were determined. The superlattice phonon frequencies show only classical behavior, it means frequency hardening on cooling. Anisotropy was also found in the superlattice phonon frequencies and their contributions to static permittivity.
Permanent Link: http://hdl.handle.net/11104/0243839