%0 Journal Article %T Unexpectedly high Curie temperature in weakly strained ferroelectric film %+ Laboratoire de Physique de la Matière Condensée - UR UPJV 2081 (LPMC) %+ Faculty of Physics %A Razumnaya, Anna G. %A Mikheykin, Alexey S. %A Lukyanchuk, Igor A. %A Shirokov, Vladimir B. %A Golovko, Yury I. %A Mukhortov, Vladimir M. %A El Marssi, Mimoun %A Yuzyuk, Yury I. %Z International Conference on Terahertz Emission, Metamaterials and Nanophotonics (TERAMETANANO), Cartagena de Indias, COLOMBIA, APR 03-10, 2016 %< avec comité de lecture %@ 0370-1972 %J physica status solidi (b) %I Wiley %V 254 %N 4 %8 2017 %D 2017 %R 10.1002/pssb.201600413 %Z Physics [physics]/Condensed Matter [cond-mat]Journal articles %X Polarized Raman spectra of the epitaxial Ba0.4Sr0.6TiO3 film grown on MgO substrate with thickness of 600nm were studied in a broad temperature range of 80-600K and the phase transition from paraelectric to tetragonal ferroelectric phase was observed at about 500K. This critical temperature is substantially higher than that calculated from the lattice-mismatch strain theory. In addition, the predicted from the theory low-temperature orthorhombic and rhombohedral phases were not observed. We ascribe the strengthening of the tetragonal ferroelectric phase to the effect of the interface-induced build-in electric field resulted from the interface-accumulated charges. %G English %L hal-03627579 %U https://u-picardie.hal.science/hal-03627579 %~ UNIV-PICARDIE %~ U-PICARDIE %~ LPMC-UPJV