Using Landau-Ginzburg-Devonshire theory and phase-field modeling, we explore the complex interplay between a structural order parameter (oxygen octahedron rotation) and polarization in EuxSr1-xTiO3 thin films. Under a biaxially tensile strain, a low-symmetry monoclinic phase with in-plane ferroelectric polarization is found to be stabilized by antiferrodistortive oxygen octahedra tilts. The monoclinic phase is stable over a wide temperature range. It is characterized by a large number of energetically equivalent polar and structural twin domains. This work demonstrates the development of a spontaneous polarization and piezo- and pyroelectricity in a ferroelastic twin boundary arising from flexoelectric coupling and rotostriction.
A. N. Morozovska et al., "Low-Symmetry Monoclinic Ferroelectric Phase Stabilized by Oxygen Octahedra Rotations in Strained EuxSr1-xTiO₃ Thin Films," Physical Review B - Condensed Matter and Materials Physics, vol. 87, no. 13, American Physical Society (APS), Apr 2013.
The definitive version is available at https://doi.org/10.1103/PhysRevB.87.134102
Mechanical and Aerospace Engineering
Keywords and Phrases
Europium; Phase transitions; Antiferromagnetism
International Standard Serial Number (ISSN)
Article - Journal
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