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arXiv · 2608.00167

Rhombohedral Graphene: A Tale of Many Crystals

Ahmed Abouelkomsan·Filippo Gaggioli·Daniele Guerci·Liang Fu
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Abstract

Experiments on rhombohedral graphene have uncovered an extraordinary wealth of correlated quantum phases - from chiral superconductors to electronic crystals - all within a single family of atomically thin materials. Here, we introduce a simple indicator, derived from the noninteracting band dispersion, that identifies strongly correlated regions in the phase diagram of rhombohedral graphene as a function of carrier density and displacement field. We develop a neural-network variational Monte Carlo method, combined with Hartree-Fock theory, to solve the interacting ground states. Our calculation reveals a variety of electron crystals with no classical analog. These include, at increasing density: Wigner crystal, self-doped Wiger crystal, as well as ''anticrystal'', a lattice of holes in an electron liquid. We discuss their experimental manifestations and possible connection to superconductivity.

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Ahmed Abouelkomsan, Filippo Gaggioli, Daniele Guerci, Liang Fu. 2026-07-31. Rhombohedral Graphene: A Tale of Many Crystals. https://arxiv.org/abs/2608.00167

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