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

ABSTRACT: Ferroelectricity (Valasek, J. Phys. Rev. 1921, 17, 475), a spontaneous formation of electric polarization, 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 polarization, 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 polarization 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 polarization.

SUBMITTER: Garcia-Ruiz A

PROVIDER: S-EPMC10214444 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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

Garcia-Ruiz Aitor A Enaldiev Vladimir V McEllistrim Andrew A Fal'ko Vladimir I VI

Nano letters 20230509 10

Ferroelectricity (Valasek, J. <i>Phys. Rev.</i> 1921, 17, 475), a spontaneous formation of electric polarization, 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 polarization, switchable by sliding the constituent graphene sheets. The systems hosting such effect include mixed-stacking tetralayers and thicker (5-9 layers) rhombohedral gr ...[more]

PMID: 37158207

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