Family of Unconventional Superconductivities in Crystalline Graphene

Junseok Seo; Armel A. Cotten; Mingchi Xu; Omid Sharifi Sedeh; Henok Weldeyesus; Tonghang Han; Zhengguang Lu; Zhenghan Wu; Shenyong Ye; Wei Xu; Jixiang Yang; Emily Aitken; Prayoga P. Liong; Zach Hadjri; Rasul Gazizulin; Kenji Watanabe; Takashi Taniguchi; Mingda Li; Dominik M. Zumbühl; Long Ju

doi:10.1038/s41586-026-10815-x

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arXiv · 2509.03295

Family of Unconventional Superconductivities in Crystalline Graphene

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Abstract

Unconventional superconductors exhibit multiple broken symmetries and exceed the range of the Bardeen-Cooper-Schrieffer (BCS) theory. For instance, time-reversal symmetry can be broken in addition to the gauge symmetry, resulting in superconductors that can be enhanced or induced by a magnetic field. However, such unconventional superconductivities are more vulnerable to impurities than their BCS counterparts, requiring highly ordered and clean material systems to observe them. Crystalline rhombohedral multilayer graphene is a promising platform to explore unconventional superconductivity due to its superior material quality and gate-tunable strong correlation effects. Here we report transport measurements of rhombohedral tetralayer and pentalayer graphene, where a spectrum of superconductivities in a clean limit are observed. Three of them (SC2-4) show highly unusual enhancements by magnetic fields: 1. SC2 is strengthened by an in-plane field; 2. SC3 is boosted by a small out-of-plane field; 3. SC4 is induced by an in-plane field. All these superconductors are robust against an in-plane field up to 8.5 Tesla, exceeding the Pauli limit of conventional superconductors by tens of times and suggesting their unconventional nature. Moreover, we observed that proximitized spin-orbit coupling generates a plethora of new superconductors in the phase diagram, while maintaining the high quality of bare rhombohedral graphene. Our work establishes a family of new superconductors in rhombohedral multilayer graphene, which also provides an ideal platform to engineer non-Abelian quasiparticles by proximitizing with quantum anomalous Hall states existing in the same material system.

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Junseok Seo, Armel A. Cotten, Mingchi Xu, Omid Sharifi Sedeh, Henok Weldeyesus, Tonghang Han, Zhengguang Lu, Zhenghan Wu, Shenyong Ye, Wei Xu, Jixiang Yang, Emily Aitken, Prayoga P. Liong, Zach Hadjri, Rasul Gazizulin, Kenji Watanabe, Takashi Taniguchi, Mingda Li, Dominik M. Zumbühl, Long Ju. 2025-09-03. Family of Unconventional Superconductivities in Crystalline Graphene. https://doi.org/10.1038/s41586-026-10815-x

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