TY - JOUR
KW - Modeling
KW - Electricity
KW - Methodology
KW - Electron microscopy
KW - Crystal structure
KW - Titanium dioxide
KW - Polarization
KW - Machine learning
KW - Experimental study
KW - Unclassified drug
KW - Article
KW - Chemical structure
KW - Lead titanate
KW - Strontium
KW - Electrical property
KW - Molecular model
KW - Strontium titanate
KW - Organolead compound
KW - Computer vision
KW - Data set
KW - Electricity generation
KW - Identification method
KW - Inorganic compound
KW - Vortex
KW - Computer analysis
KW - Flexoelectricity
KW - Quantitative analysis
KW - Vortex motion
AU - Q Li
AU - C.T Nelson
AU - S.-L Hsu
AU - A.R Damodaran
AU - L.-L Li
AU - A.K Yadav
AU - M McCarter
AU - L.W Martin
AU - Ramamoorthy Ramesh
AU - S.V Kalinin
AB - Flexoelectricity refers to electric polarization generated by heterogeneous mechanical strains, namely strain gradients, in materials of arbitrary crystal symmetries. Despite more than 50 years of work on this effect, an accurate identification of its coupling strength remains an experimental challenge for most materials, which impedes its wide recognition. Here, we show the presence of flexoelectricity in the recently discovered polar vortices in PbTiO3/SrTiO3 superlattices based on a combination of machine-learning analysis of the atomic-scale electron microscopy imaging data and phenomenological phase-field modeling. By scrutinizing the influence of flexocoupling on the global vortex structure, we match theory and experiment using computer vision methodologies to determine the flexoelectric coefficients for PbTiO3 and SrTiO3. Our findings highlight the inherent, nontrivial role of flexoelectricity in the generation of emergent complex polarization morphologies and demonstrate a viable approach to delineating this effect, conducive to the deeper exploration of both topics. © 2017 The Author(s).
BT - Nature Communications
DO - 10.1038/s41467-017-01733-8
LA - eng
M1 - 1
N1 - cited By 27
N2 - Flexoelectricity refers to electric polarization generated by heterogeneous mechanical strains, namely strain gradients, in materials of arbitrary crystal symmetries. Despite more than 50 years of work on this effect, an accurate identification of its coupling strength remains an experimental challenge for most materials, which impedes its wide recognition. Here, we show the presence of flexoelectricity in the recently discovered polar vortices in PbTiO3/SrTiO3 superlattices based on a combination of machine-learning analysis of the atomic-scale electron microscopy imaging data and phenomenological phase-field modeling. By scrutinizing the influence of flexocoupling on the global vortex structure, we match theory and experiment using computer vision methodologies to determine the flexoelectric coefficients for PbTiO3 and SrTiO3. Our findings highlight the inherent, nontrivial role of flexoelectricity in the generation of emergent complex polarization morphologies and demonstrate a viable approach to delineating this effect, conducive to the deeper exploration of both topics. © 2017 The Author(s).
PB - Nature Publishing Group
PY - 2017
T2 - Nature Communications
TI - Quantification of flexoelectricity in PbTiO3/SrTiO3 superlattice polar vortices using machine learning and phase-field modeling
VL - 8
SN - 20411723
ER -