Atomic-scale observations of electrical and mechanical manipulation of topological polar flux closure

The ability to controllably manipulate complex topological polar configurations such as polar flux-closures via external stimuli may allow the construction of new electromechanical and nanoelectronic devices. Here, using atomically resolved in situ scanning transmission electron microscopy, we find...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2020-08, Vol.117 (32), p.18954-18961
Main Authors: Li, Xiaomei, Tan, Congbing, Liu, Chang, Gao, Peng, Sun, Yuanwei, Chen, Pan, Li, Mingqiang, Liao, Lei, Zhu, Ruixue, Wang, Jinbin, Zhao, Yanchong, Wang, Lifen, Xu, Zhi, Liu, Kaihui, Zhong, Xiangli, Wang, Jie, Bai, Xuedong
Format: Article
Language:English
Subjects:
Closures
Domain walls
Electric fields
External stimuli
Ferroelectric materials
Ferroelectricity
Fluctuations
Flux
Lead titanates
Movement
Nanoelectronics
Nanotechnology devices
Phase transitions
Physical Sciences
Scanning transmission electron microscopy
Strontium titanates
Superlattices
Topology
Transmission electron microscopy
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The ability to controllably manipulate complex topological polar configurations such as polar flux-closures via external stimuli may allow the construction of new electromechanical and nanoelectronic devices. Here, using atomically resolved in situ scanning transmission electron microscopy, we find that the polar fluxclosures in PbTiO₃/SrTiO₃ superlattice films are mobile and can be reversibly switched to ordinary single ferroelectric c or a domains under an applied electric field or stress. Specifically, the electric field initially drives movement of a flux-closure via domain wall motion and then breaks it to form intermediate a/c striped domains, whereas mechanical stress first squeezes the core of a flux-closure toward the interface and then form a/c domains with disappearance of the core. After removal of the external stimulus, the flux-closure structure spontaneously recovers. These observations can be precisely reproduced by phase field simulations, which also reveal the evolutions of the competing energies during phase transitions. Such reversible switching between flux-closures and ordinary ferroelectric states provides a foundation for potential electromechanical and nanoelectronic applications.
ISSN:0027-8424
1091-6490
DOI:10.1073/pnas.2007248117