Fractional Chern mosaic in supermoir\'e graphene

Yves H. Kwan; Tixuan Tan; Trithep Devakul

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arXiv · 2411.08880

Fractional Chern mosaic in supermoir\'e graphene

Yves H. Kwan·Tixuan Tan·Trithep Devakul

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Abstract

We propose the realization of a fractional Chern mosaic: a state characterized by a spatially varying topological order. This state is enabled by a separation of length scales that emerges when three graphene sheets are sequentially rotated by a small twist angle. The resulting structure features not only conventional moir\'e lattices, but also a much larger supermoir\'e lattice. We demonstrate that a fractional Chern mosaic arises when electron correlations induce fractionalization locally on the moir\'e scale, while the pattern of fractionalization varies at the supermoir\'e scale.

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Yves H. Kwan, Tixuan Tan, Trithep Devakul. 2024-11-13. Fractional Chern mosaic in supermoir\'e graphene. https://arxiv.org/abs/2411.08880

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