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.
@article{arxiv.1106.3792,
title = {Giant Flexoelectric Effect in Ferroelectric Epitaxial Thin Films},
author = {Daesu Lee and A. Yoon and S. Y. Jang and J. -G. Yoon and J. -S. Chung and M. Kim and J. F. Scott and T. W. Noh},
journal= {arXiv preprint arXiv:1106.3792},
year = {2011}
}