Strain-driven phase transitions and associated dielectric/piezoelectric anomalies in BiFeO3 thin films

Applied Physics Letters (Impact Factor: 3.52). 11/2010; DOI: 10.1063/1.3499658
Source: IEEE Xplore

ABSTRACT Strain-driven phase transitions and related intrinsic polarization, dielectric, and piezoelectric properties for single-domain films were studied for BiFeO 3 using phenomenological Landau–Devonshire theory. A stable and mixed structure between tetragonal and rhombohedral-like (monoclinic) phases is predicted at a compressive misfit strain of um=-0.0382 without an energy barrier. For a tensile misfit strain of um=0.0272 , another phase transition between the monoclinic and orthorhombic phases was predicted with sharply high dielectric and piezoelectric responses.

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