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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Macroscopic self-reorientation of interacting two-dimensional crystals.
C R Woods1, F Withers1, M J Zhu1
1School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK.
Nature Communications
|March 11, 2016
Summary
Graphene on hexagonal boron nitride self-rotates due to van der Waals and elastic forces, enabling precise alignment for manufacturing van der Waals heterostructures.
Area of Science:
- Materials Science
- Nanotechnology
- Condensed Matter Physics
Background:
- Microelectromechanical systems (MEMS) offer precise motion control at the nanoscale.
- Atomic-level forces and self-alignment mechanisms are key for advanced MEMS applications.
- Controlled movements in response to external parameter changes are crucial for MEMS functionality.
Purpose of the Study:
- To investigate the self-alignment mechanisms in graphene on hexagonal boron nitride systems.
- To demonstrate the potential of atomic-scale forces for controlled macroscopic movements.
- To explore the application of these phenomena in the reproducible manufacturing of aligned van der Waals heterostructures.
Main Methods:
- Studied the interplay between van der Waals and elastic energies in graphene/hexagonal boron nitride systems.
- Observed and quantified the mechanical self-rotation of graphene flakes.
- Analyzed the crystallographic alignment driven by atomic-level interactions.
Main Results:
- Graphene mechanically self-rotates towards hexagonal boron nitride crystallographic directions.
- This rotation is a macroscopic phenomenon, with tangential movements up to hundreds of nanometres for micrometer-sized flakes.
- The observed self-rotation is driven by the combined van der Waals and elastic energies.
Conclusions:
- The van der Waals and elastic energy interplay drives self-alignment in graphene/hBN systems.
- This controllable nanoscale phenomenon enables macroscopic, reproducible alignment of van der Waals heterostructures.
- Offers a novel pathway for fabricating precisely aligned 2D material-based devices.
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