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arXiv · 2002.07790

Long-range rhombohedral-stacked graphene through shear

Jean Paul Nery·Matteo Calandra·Francesco Mauri
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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.

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Jean Paul Nery, Matteo Calandra, Francesco Mauri. 2020-02-18. Long-range rhombohedral-stacked graphene through shear. https://doi.org/10.1021/acs.nanolett.0c01146

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