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arXiv · 1204.2958

Can we trust the temperature - misfit strain thin film phase diagrams?

Alexander Kvasov·Alexander K. Tagantsev
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Abstract

Currently used methods for the description of thermodynamics of ferroelectric thin films (Landau theory or ab initio based Monte-Carlo simulations) are based on an energy expansion in terms of internal degrees of freedom. It was shown that these methods can suffer from a substantial inaccuracy unless higher-order electromechanical interactions are not taken into account. The high-order electromechanical couplings strongly renormalize the sixth-power polarization terms of the thermodynamic energy expansion. In this paper, apart from the general statement, we illustrate it with an example of a temperature - misfit strain phase diagram of a BaTiO3 thin film derived with high-order electromechanical interactions evaluated using first principles calculations.

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Alexander Kvasov, Alexander K. Tagantsev. 2012-04-13. Can we trust the temperature - misfit strain thin film phase diagrams?. https://doi.org/10.1103/physrevb.87.184101

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