Direct transition from the rhombohedral ferroelectric to the paraelectric phase in a (Ba,Sr)TiO3 thin film on a (111)MgO substrate

• Published in: Europhysics letters Vol. 112; no. 4; pp. 47001 - 47006
• Main Authors: Anokhin, A. S., Yuzyuk, Yu. I., Lyanguzov, N. V., Razumnaya, A. G., Stryukov, D. V., Bunina, O. A., Golovko, Yu. I., Shirokov, V. B., Mukhortov, V. M., El Marssi, M.
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences, IOP Publishing and Società Italiana di Fisica 01.11.2015; IOP Publishing
• Subjects: 77.55.fe; 78.30.-j; Epitaxial growth; Ferroelectric materials; Ferroelectricity; Magnesium oxide; Phase transitions; Raman spectra; Room temperature; Substrates; Temperature dependence; Thin films
• ISSN: 0295-5075; 1286-4854
• DOI: 10.1209/0295-5075/112/47001

A heteroepitaxial (200 nm thick) (BST) thin film was deposited on a (111)MgO substrate using rf sputtering. X-ray diffraction examinations confirmed epitaxial growth and rhombohedral symmetry of the film ( and ) at room temperature. Polarized Raman spectra of the film were studied in the temperature range from 100 to 420 K. In contrast to a BST thin film grown on (001)MgO, the observed linear temperature dependence of the squared soft mode frequency suggests the displacive character of the ferroelectric-paraelectric phase transition in a BST thin film on (111)MgO.