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In situ manipulation of van der Waals heterostructures for twistronics.

ABSTRACT: In van der Waals heterostructures, electronic bands of two-dimensional (2D) materials, their nontrivial topology, and electron-electron interactions can be markedly changed by a moiré pattern induced by twist angles between different layers. This process is referred to as twistronics, where the tuning of twist angle can be realized through mechanical manipulation of 2D materials. Here, we demonstrate an experimental technique that can achieve in situ dynamical rotation and manipulation of 2D materials in van der Waals heterostructures. Using this technique, we fabricated heterostructures where graphene is perfectly aligned with both top and bottom encapsulating layers of hexagonal boron nitride. Our technique enables twisted 2D material systems in one single stack with dynamically tunable optical, mechanical, and electronic properties.

SUBMITTER: Yang Y

PROVIDER: S-EPMC7717928 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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In situ manipulation of van der Waals heterostructures for twistronics.

Yang Yaping Y Li Jidong J Yin Jun J Xu Shuigang S Mullan Ciaran C Taniguchi Takashi T Watanabe Kenji K Geim Andre K AK Novoselov Konstantin S KS Mishchenko Artem A

Science advances 20201204 49

In van der Waals heterostructures, electronic bands of two-dimensional (2D) materials, their nontrivial topology, and electron-electron interactions can be markedly changed by a moiré pattern induced by twist angles between different layers. This process is referred to as twistronics, where the tuning of twist angle can be realized through mechanical manipulation of 2D materials. Here, we demonstrate an experimental technique that can achieve in situ dynamical rotation and manipulation of 2D mat ...[more]

PMID: 33277256

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