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Correlated States in Strained Twisted Bilayer Graphenes Away from the Magic Angle.

ABSTRACT: Graphene moiré superlattice formed by rotating two graphene sheets can host strongly correlated and topological states when flat bands form at so-called magic angles. Here, we report that, for a twisting angle far away from the magic angle, the heterostrain induced during stacking heterostructures can also create flat bands. Combining a direct visualization of strain effect in twisted bilayer graphene moiré superlattices and transport measurements, features of correlated states appear at "non-magic" angles in twisted bilayer graphene under the heterostrain. Observing correlated states in these "non-standard" conditions can enrich the understanding of the possible origins of the correlated states and widen the freedom in tuning the moiré heterostructures and the scope of exploring the correlated physics in moiré superlattices.

SUBMITTER: Zhang L

PROVIDER: S-EPMC9052762 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Correlated States in Strained Twisted Bilayer Graphenes Away from the Magic Angle.

Zhang Le L Wang Ying Y Hu Rendong R Wan Puhua P Zheliuk Oleksandr O Liang Minpeng M Peng Xiaoli X Zeng Yu-Jia YJ Ye Jianting J

Nano letters 20220406 8

Graphene moiré superlattice formed by rotating two graphene sheets can host strongly correlated and topological states when flat bands form at so-called magic angles. Here, we report that, for a twisting angle far away from the magic angle, the heterostrain induced during stacking heterostructures can also create flat bands. Combining a direct visualization of strain effect in twisted bilayer graphene moiré superlattices and transport measurements, features of correlated states appear at "non-ma ...[more]

PMID: 35385281

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