Realization of correlated and topological electronic states in crystalline graphene

Guorui Chen

doi:10.61109/cs.202508.150

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Realization of correlated and topological electronic states in crystalline graphene

DOI: https://doi.org/10.61109/cs.202508.150

Coshare Science 03, 03 | Published 29 August 2025 |

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G. Chen, Realization of correlated and topological electronic states in crystalline graphene, Coshare Science 03, 03 (2025).

Abstract

Electron-electron interactions can be significant in graphene with an ABC-stacking sequence. By developing innovative experimental techniques, we successfully fabricated high-quality ABC-stacked multilayer graphene and observed a correlated insulating state at charge neutrality, beginning with ABCA-tetralayer. Furthermore, by introducing proximity-induced spin-orbit coupling, at the charge neutrality point of ABCA-tetralayer, we achieved a topological Chern insulator with a layer-number-dependent Chern number of four.

Keywords

layer stacking

multilayer graphene

strong correlation

Chern insulator

Introduction

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Result and discussion

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Conclusions

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Declarations

The author declares no competing interests.

Acknowledgements

The work at SJTU was supported by National Key Research Program of China (Grant Nos. 2021YFA1400100 and 2020YFA0309000), NSF of China (Grant Nos. 12350005 and 12174248), Shanghai Science and Technology Innovation Action Plan (Grant No. 24LZ1401100) and the Yangyang Development Fund.

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