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Long-Range Rhombohedral-Stacked Graphene through Shear.

ABSTRACT: The discovery of superconductivity and correlated electronic states in the flat bands of twisted bilayer graphene has raised a lot of excitement. Flat bands also occur in multilayer graphene flakes that present rhombohedral (ABC) stacking order on many consecutive layers. Although Bernal-stacked (AB) graphene is more stable, long-range ABC-ordered flakes involving up to 50 layers have been surprisingly observed in natural samples. Here, we present a microscopic atomistic model, based on first-principles density functional theory calculations, that demonstrates how shear stress can produce long-range ABC order. A stress-angle phase diagram shows under which conditions ABC-stacked graphene can be obtained, providing an experimental guide for its synthesis.

SUBMITTER: Nery JP

PROVIDER: S-EPMC8008449 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Long-Range Rhombohedral-Stacked Graphene through Shear.

Nery Jean Paul JP Calandra Matteo M Mauri Francesco F

Nano letters 20200617 7

The discovery of superconductivity and correlated electronic states in the flat bands of twisted bilayer graphene has raised a lot of excitement. Flat bands also occur in multilayer graphene flakes that present rhombohedral (ABC) stacking order on many consecutive layers. Although Bernal-stacked (AB) graphene is more stable, long-range ABC-ordered flakes involving up to 50 layers have been surprisingly observed in natural samples. Here, we present a microscopic atomistic model, based on first-pr ...[more]

PMID: 32525317

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