Geometric origin of spontaneous chiral symmetry breaking in rhombohedral graphene

Spontaneous chiral symmetry breaking was predicted in charge-neutral rhombohedral graphene systems [1]. The predicted broken symmetry states, such as layer antiferromagnetic states and quantum anomalous Hall states of large Chern numbers, were experimentally observed in a variety of devices of different dielectric environments and different layer thickness [2-7]. We investigate the geometric origin of this weak interaction instability, elucidate its universal robustness, and identify a potential pathway for developing correlated topological phases of matter.

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