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Updated: Jul 8, 2025
14:52
Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding
Published on: September 23, 2018
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Non-identical moiré twins in bilayer graphene
Everton Arrighi1, Viet-Hung Nguyen2, Mario Di Luca1
1Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies (C2N), 91120, Palaiseau, France.
Nature Communications
|December 11, 2023
Summary
Graphene and boron nitride (BN) superlattices show different electronic properties at 0° and 60° alignments. Atomic structure relaxation explains these moiré twins, but not the observed valley Hall effect.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Hexagonal lattices like graphene and boron nitride (BN) exhibit 60° periodicity.
- Aligned heterostructures are expected to have identical properties regardless of layer twist angle.
Purpose of the Study:
- Investigate the electronic properties of graphene/BN moiré superlattices at different alignment angles.
- Explain the origin of observed electronic phenomena in twisted heterostructures.
Main Methods:
- Fabrication of dynamically rotatable van der Waals heterostructures.
- Analysis of atomic structure relaxation in graphene/BN bilayers.
- Experimental observation of electronic properties, including the valley Hall effect.
Main Results:
- Graphene/BN moiré superlattices exhibit distinct electronic properties at 0° and 60° alignments.
- Atomic structure relaxation differs between the 0° and 60° alignments, creating non-identical moiré twins.
- A simple Berry curvature model fails to explain the observed 120° periodicity of the valley Hall effect.
Conclusions:
- The interplay between mechanical and electronic properties in moiré structures is complex.
- Atomic structure relaxation is crucial for understanding the electronic behavior of these heterostructures.
- Further theoretical investigation is needed to explain the valley Hall effect in graphene/BN systems.
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