Superconductivity in twisted multilayer graphene: A smoking gun in recent condensed matter physics

doi:10.1088/1674-1056/abbbea

摘要/Abstract

Abstract:

We review the recent discoveries of exotic phenomena in graphene, especially superconductivity. It has been theoretically suggested for more than one decade that superconductivity may emerge in doped graphene-based materials. For single-layer pristine graphene, there are theoretical predictions that spin-singlet d + id pairing superconductivity is present when the filling is around the Dirac point. If the Fermi level is doped to the Van Hove singularity where the density of states diverges, then unconventional superconductivity with other pairing symmetry would appear. However, the experimental perspective was a bit disappointing. Despite extensive experimental efforts, superconductivity was not found in monolayer graphene. Recently, unconventional superconductivity was found in magic-angle twisted bilayer graphene. Superconductivity was also found in ABC stacked trilayer graphene and other systems. In this article, we review the unique properties of superconducting states in graphene, experimentally controlling the superconductivity in twisted bilayer graphene, as well as a gate-tunable Mott insulator, and the superconductivity in trilayer graphene. These discoveries have attracted the attention of a large number of physicists. The study of the electronic correlated states in twisted multilayer graphene serves as a smoking gun in recent condensed matter physics.

Key words: graphene, twisted multilayer graphene, superconductivity

Yonghuan Chu(楚永唤), Fangduo Zhu(朱方铎), Lingzhi Wen(温凌志), Wanying Chen(陈婉莹), Qiaoni Chen(陈巧妮), Tianxing Ma(马天星). [J]. 中国物理B, 2020, 29(11): 117401-.

Yonghuan Chu(楚永唤), Fangduo Zhu(朱方铎), Lingzhi Wen(温凌志), Wanying Chen(陈婉莹), Qiaoni Chen(陈巧妮), and Tianxing Ma(马天星). Superconductivity in twisted multilayer graphene: A smoking gun in recent condensed matter physics[J]. Chin. Phys. B, 2020, 29(11): 117401-.

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