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arXiv · 1105.4001

Nanoscale structure and mechanism for enhanced electromechanical response of highly-strained BiFeO3 thin films

A. R. Damodaran·C. -W. Liang·Q. He·C. -Y. Peng·L. Chang·Y. -H. Chu·L. W. Martin
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Abstract

The nanostructural evolution of the strain-induced structural phase transition in BiFeO3 is examined. Using high-resolution X-ray diffraction and scanning-probe microscopy-based studies we have uniquely identified and examined the numerous phases present at these phase boundaries and have discovered an intermediate monoclinic phase in addition to the previously observed rhombohedral- and tetragonal-like phases. Further analysis has determined that the so-called mixed-phase regions of these films are not mixtures of rhombohedral- and tetragonal-like phases, but intimate mixtures of highly-distorted monoclinic phases with no evidence for the presence of the rhombohedral-like parent phase. Finally, we propose a mechanism for the enhanced electromechanical response in these films including how these phases interact at the nanoscale to produce large surface strains.

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A. R. Damodaran, C. -W. Liang, Q. He, C. -Y. Peng, L. Chang, Y. -H. Chu, L. W. Martin. 2011-05-20. Nanoscale structure and mechanism for enhanced electromechanical response of highly-strained BiFeO3 thin films. https://arxiv.org/abs/1105.4001

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