Revealing the flexoelectricity in the mixed-phase regions of epitaxial BiFeO3 thin films

Year: 2015

Authors: Cheng C.E., Liu H.J., Dinelli F., Chen Y.C., Chang C.S., Chien F: S.S., Chu Y.H.

Autors Affiliation: Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Hsinchu, 30010, Taiwan; Department of Applied Physics, Tunghai University, Taichung, 40704, Taiwan; Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, 30010, Taiwan; Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica, I-56124 Pisa, Italy; Department of Physics, National Cheng Kung University, Tainan, 701, Taiwan

Abstract: Understanding the elastic response on the nanoscale phase boundaries of multiferroics is an essential issue in order to explain their exotic behaviour. Mixed-phase BiFeO3 films, epitaxially grown on LaAlO3 (001) substrates, have been investigated by means of scanning probe microscopy to characterize the elastic and piezoelectric responses in the mixed-phase region of rhombohedral-like monoclinic (M-I) and tilted tetragonal-like monoclinic (M-II,M-tilt) phases. Ultrasonic force microscopy reveal that the regions with low/ high stiffness values topologically coincide with the M-I/M-II,M-tilt phases. X-ray diffraction strain analysis confirms that the M-I phase is more compliant than the M-II,(tilt) one. Significantly, the correlation between elastic modulation and piezoresponse across the mixed-phase regions manifests that the flexoelectric effect results in the enhancement of the piezoresponse at the phase boundaries and in the M-I regions. This accounts for the giant electromechanical effect in strained mixed-phase BiFeO3 films.


Volume: 5      Pages from: 8091-1  to: 8091-5

More Information: This work is supported by Ministry of Science and Technology of Taiwan (Grant NO. MOST 102-2112-M-029-005-MY3), and National Chiao Tung University (2013 NCTU Short-term Research Program Scholarship). The authors would like to thank Dr. P. Pinque of NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore for his kindly support.
DOI: 10.1038/srep08091

Citations: 28
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-05-26
References taken from IsiWeb of Knowledge: (subscribers only)
Connecting to view paper tab on IsiWeb: Click here
Connecting to view citations from IsiWeb: Click here