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Smearing of phase transition due to a surface effect or a bulk inhomogeneity in ferroelectric nanostructures

A. M. Bratkovsky·A. P. Levanyuk
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Abstract

The boundary conditions, customarily used in the Landau-type approach to ferroelectric thin films and nanostructures, have to be modified to take into account that a surface of a ferroelectric (FE) is a defect of the ``field'' type. The surface (interface) field is coupled to a normal component of polarization and, as a result, the second order phase transitions are generally suppressed and anomalies in response are washed out. In FE films with a compositional (grading) or some other type of inhomogeneity, the transition into a monodomain state is suppressed, but a transition with formation of a domain structure may occur.

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A. M. Bratkovsky, A. P. Levanyuk. 2004-02-09. Smearing of phase transition due to a surface effect or a bulk inhomogeneity in ferroelectric nanostructures. https://doi.org/10.1103/physrevlett.94.107601

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