Correlated topological flat bands in rhombohedral graphite
Flat bands and nontrivial topological physics are two important topics of condensed matter physics. With a unique stacking configuration analogous to the Su-Schrieffer-Heeger model, rhombohedral graphite (RG) is a potential candidate for realizing both flat bands and nontrivial topological physics. Here, we report experimental evidence of topological flat bands (TFBs) on the surface of bulk RG, which are topologically protected by bulk helical Dirac nodal lines via the bulk-boundary correspondence. Moreover, upon in situ electron doping, the surface TFBs show a splitting with exotic doping evolution, with an order-of-magnitude increase in the bandwidth of the lower split band, and pinning of the upper band near the Fermi level. These experimental observations together with Hartree-Fock calculations suggest that correlation effects are important in this system. Our results demonstrate RG as a platform for investigating the rich interplay between nontrivial band topology, correlation effects, and interaction-driven symmetry-broken states.
Authors
- Peizhe Tang (ORCID: https://orcid.org/0000-0002-6345-5809)
- Shuyun Zhou (ORCID: https://orcid.org/0000-0002-9841-8610)
- Hong Yao (ORCID: https://orcid.org/0000-0003-2867-6144)
- Pavel Dudin (ORCID: https://orcid.org/0000-0002-5971-0395)
- Chuyi Tuo
- Wenhui Duan (ORCID: https://orcid.org/0000-0001-9685-2547)
- Ming-Rui Li (ORCID: https://orcid.org/0000-0001-5453-1948)
- Wanying Chen (ORCID: https://orcid.org/0000-0002-8650-4888)
- Takashi Taniguchi (ORCID: https://orcid.org/0000-0002-1467-3105)
- Biao Lian (ORCID: https://orcid.org/0000-0002-8956-5619)
- Kenji Watanabe (ORCID: https://orcid.org/0000-0003-3701-8119)
- Pu Yu (ORCID: https://orcid.org/0000-0002-5513-7632)
- Michael G. Scheer (ORCID: https://orcid.org/0000-0003-0798-6135)
- Jonathan D. Denlinger (ORCID: https://orcid.org/0000-0001-7645-1631)
- Qian Li (ORCID: https://orcid.org/0000-0003-1452-7121)
- R.Z. Wang (ORCID: https://orcid.org/0009-0008-8682-0531)
- J. Ávila (ORCID: https://orcid.org/0000-0003-1027-5676)
- Ke Deng (ORCID: https://orcid.org/0000-0001-5656-8867)
- Xuanxi Cai (ORCID: https://orcid.org/0009-0004-6444-9541)
- Nianlong Zou (ORCID: https://orcid.org/0000-0002-8746-8970)
- Changhua Bao (ORCID: https://orcid.org/0000-0002-8706-6541)
- Mao Ye (ORCID: https://orcid.org/0000-0002-3298-4724)
- Jiaheng Li (ORCID: https://orcid.org/0000-0003-0130-4615)
- Hong‐Yun Zhang (ORCID: https://orcid.org/0000-0002-0993-8949)
- Yong Xu (ORCID: https://orcid.org/0000-0003-4946-6664)
Institutions
- Lawrence Berkeley National Laboratory (US)
- Universität Hamburg (DE)
- Chinese Academy of Sciences (CN)
- Princeton University (US)
- National Institute for Materials Science (JP)
- Synchrotron soleil (FR)
- Shanghai Advanced Research Institute (CN)
- Center for Free-Electron Laser Science (DE)
- Max Planck Institute for the Structure and Dynamics of Matter (DE)
- Beijing Academy of Quantum Information Sciences (CN)
- State Key Laboratory of Low-Dimensional Quantum Physics
- Beihang University (CN)
- Tsinghua University (CN)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2024-10-16
- DOI
- https://doi.org/10.1073/pnas.2410714121
- Citations
- 10
- Primary Topic
- Graphene research and applications
- Type
- article
- Field-Weighted Citation Impact
- 1.17
Funders
- National Science Foundation
- U.S. Department of Energy
- Princeton University
- Ministry of Education, Culture, Sports, Science and Technology
- National Natural Science Foundation of China
- China Postdoctoral Science Foundation
- Office of Science
- Japan Society for the Promotion of Science
- Division of Materials Research