Giant Polarization and Abnormal Flexural Deformation in Bent Freestanding Perovskite Oxides
Abstract
Recent realizations of ultrathin freestanding perovskite oxides offer a unique platform to probe novel properties in two-dimensional oxides. Here, we observed a giant flexoelectric response in freestanding BiFeO3 and SrTiO3 in their bent state arising from strain gradients up to 4x10e7/m, suggesting a promising approach for realizing extremely large polarizations. Additionally, a substantial reversible change in thickness was discovered in bent freestanding BiFeO3, which implies an unusual bending-expansion/shrinkage and thickness-dependence Poisson's ratios in this ferroelectric membrane that has never been seen before in crystalline materials. Our theoretical modeling reveals that this unprecedented flexural deformation within the membrane is attributable to a flexoelectricity-piezoelectricity interplay. The finding unveils intriguing nanoscale electromechanical properties and provides guidance for their practical applications in flexible nanoelectromechanical systems.
Keywords
Cite
@article{arxiv.2009.03177,
title = {Giant Polarization and Abnormal Flexural Deformation in Bent Freestanding Perovskite Oxides},
author = {Songhua Cai and Yingzhuo Lun and Dianxiang Ji and Lu Han and Changqing Guo and Yipeng Zang and Si Gao and Yifan Wei and Min Gu and Chunchen Zhang and Zhengbin Gu and Xueyun Wang and Christopher Addiego and Daining Fang and Yuefeng Nie and Jiawang Hong and Peng Wang and Xiaoqing Pan},
journal= {arXiv preprint arXiv:2009.03177},
year = {2020}
}
Comments
19 pages, 4 figures