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Phenomenological theory of phase transitions in epitaxial BaTiO3 thin films

V. B. Shirokov·Yu. I. Yuzyuk·B. Dkhil·V. V. Lemanov
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Abstract

We develop a phenomenological thermodynamic theory of ferroelectric BaTiO3 (BT) thin films epitaxially grown on cubic substrates using the Landau-Devonshire eight-order potential. The constructed "misfit-temperature" phase diagram is asymmetrical. We found that, overall view of the phase diagram depends on the values of compliances used in calculations and provide two qualitatively different diagrams. A thermodynamic path for BT film grown onto particular substrate can be found using a plot of the room-temperature tetragonal distortion (c-a)/a as a function of misfit strain.

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V. B. Shirokov, Yu. I. Yuzyuk, B. Dkhil, V. V. Lemanov. 2007-06-24. Phenomenological theory of phase transitions in epitaxial BaTiO3 thin films. https://doi.org/10.1103/physrevb.75.224116

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