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Updated: May 23, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Imaging Electric Polarization Switching in Multilayer Graphene.
Zhou Zhou1, Xiyao Peng1, Jianfeng Bi1
1School of Physics, Zhejiang Key Laboratory of Micro-Nano Quantum Chips and Quantum Control, and State Key Laboratory of Silicon and Advanced Semiconductor Materials, Zhejiang University, Hangzhou, China.
Summary
Researchers observed electric polarization switching in multilayer graphene using domain wall (DW) sliding. This novel finding in 2D sliding ferroelectricity opens new avenues for advanced electronic materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Emerging 2D sliding ferroelectricity is characterized by polarization switching via domain wall (DW) sliding.
- Multilayer graphene is gaining attention for its tunable electron correlation and band topology.
Purpose of the Study:
- To directly observe and realize domain wall sliding-induced electric polarization switching in multilayer graphene.
- To investigate the mechanism behind polarization switching in tetralayer graphene.
Main Methods:
- Utilized a gate-tunable nanoscale optical imaging technique to identify polar domains in tetralayer graphene.
- Applied global and local electric fields and mechanical forces to induce and observe DW sliding.
- Combined experimental observations with theoretical analysis.
Main Results:
- Direct observation of electric polarization switching induced by DW sliding in multilayer graphene for the first time.
- Identification of adjacent polar domains with opposite electric polarizations in tetralayer graphene.
- Determination that a single DW sliding at the middlemost interface is responsible for polarization switching.
Conclusions:
- Demonstrated domain wall sliding as a mechanism for polarization switching in multilayer graphene.
- Established a novel optical readout method for sensitive detection of electric polarization in 2D materials.
- Opened new opportunities for studying sliding ferroelectricity in graphene-based systems.
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