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arXiv · 1106.3792

Giant Flexoelectric Effect in Ferroelectric Epitaxial Thin Films

Daesu Lee·A. Yoon·S. Y. Jang·J. -G. Yoon·J. -S. Chung·M. Kim·J. F. Scott·T. W. Noh
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Abstract

We report on nanoscale strain gradients in ferroelectric HoMnO3 epitaxial thin films, resulting in a giant flexoelectric effect. Using grazing-incidence in-plane X-ray diffraction, we measured strain gradients in the films, which were 6 or 7 orders of magnitude larger than typical values reported for bulk oxides. The combination of transmission electron microscopy, electrical measurements, and electrostatic calculations showed that flexoelectricity provides a means of tuning the physical properties of ferroelectric epitaxial thin films, such as domain configurations and hysteresis curves.

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Daesu Lee, A. Yoon, S. Y. Jang, J. -G. Yoon, J. -S. Chung, M. Kim, J. F. Scott, T. W. Noh. 2011-06-20. Giant Flexoelectric Effect in Ferroelectric Epitaxial Thin Films. https://doi.org/10.1103/physrevlett.107.057602

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