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arXiv · 1012.5423

Free-standing ferroelectric multilayers: Crossover from thin-film to bulk behavior

Abstract

Ferroelectric films usually have phase states and physical properties very different from those of bulk ferroelectrics. Here we propose free-standing ferroelectric-elastic multilayers as a bridge between these two material systems. Using a nonlinear thermodynamic theory, we determine phase states of such multilayers as a function of temperature, misfit strain, and volume fraction fi of ferroelectric material. The numerical calculations performed for two classical ferroelectrics - PbTiO3 and BaTiO3 - demonstrate that polarization states of multilayers in the limiting cases fi -> 0 and fi -> 1 coincide with those of thin films and bulk crystals. At intermediate volume fractions, however, the misfit strain-temperature phase diagrams of multilayers differ greatly from those of epitaxial films. Remarkably, a ferroelectric phase not existing in thin films and bulk crystals can be stabilized in BaTiO3 multilayers. Owing to additional tunable parameter and reduced clamping, ferroelectric multilayers may be superior for a wide range of device applications.

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BibTeXRIS

S. Prokhorenko, N. A. Pertsev. 2010-12-24. Free-standing ferroelectric multilayers: Crossover from thin-film to bulk behavior. https://doi.org/10.1063/1.3647585

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