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arXiv · 2305.10896

Mixed-Stacking Few-Layer Graphene as an Elemental Weak Ferroelectric Material

Aitor Garcia-Ruiz·Vladimir Enaldiev·Andrew McEllistrim·Vladimir I. Fal'ko
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Abstract

Ferroelectricity (Valasek, J. Phys. Rev. 1921, 17, 475) - a spontaneous formation of electric polarisation - is a solid state phenomenon, usually, associated with ionic compounds or complex materials. Here we show that, atypically for elemental solids, few-layer graphenes can host an equilibrium out-of-plane electric polarisation, switchable by sliding the constituent graphene sheets. The systems hosting such effect include mixed-stacking tetralayers and thicker (5-9 layers) rhombohedral graphitic films with a twin boundary in the middle of a flake. The predicted electric polarisation would also appear in marginally (small-angle) twisted few-layer flakes, where lattice reconstruction would give rise to networks of mesoscale domains with alternating value and sign of out-of-plane polarisation.

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BibTeXRIS

Aitor Garcia-Ruiz, Vladimir Enaldiev, Andrew McEllistrim, Vladimir I. Fal'ko. 2023-05-18. Mixed-Stacking Few-Layer Graphene as an Elemental Weak Ferroelectric Material. https://doi.org/10.1021/acs.nanolett.2c04723

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