Suppression of symmetry-breaking correlated insulators in a rhombohedral trilayer graphene superlattice
Counterintuitive temperature dependence of isospin flavor polarization has recently been found in twisted bilayer graphene, where unpolarized electrons in a Fermi liquid become a spin-valley polarized insulator upon heating. So far, the effect has been limited to v = +/-1 (one electron/hole per superlattice cell), leaving open questions such as whether it is a general property of symmetry-breaking electronic phases. Here, by studying a rhombohedral trilayer graphene/boron nitride moiré superlattice, we report that at v = -3 a resistive peak emerges at elevated temperatures or in parallel magnetic fields. Concomitantly, the Hall carrier density tends to reset at the integer filling, signaling spin-valley flavor symmetry breaking. These phenomena can also be observed at v = -1 and -2 when the displacement field is large enough to suppress correlated insulators at low temperatures. Our results greatly expand the scope for observing the counterintuitive temperature dependence of flavor polarization, i.e., the regimes proximal to symmetry-breaking phases where the flavor polarization order strongly fluctuates, encouraging more experimental and theoretical exploration of isospin flavor polarization dynamics in flat-band moiré systems.
Authors
- Chunrui Han
- Zhida Song (ORCID: https://orcid.org/0000-0002-4987-5962)
- Jinhai Mao (ORCID: https://orcid.org/0000-0002-9034-3642)
- Qianling Liu
- Takashi Taniguchi (ORCID: https://orcid.org/0000-0002-1467-3105)
- Kenji Watanabe (ORCID: https://orcid.org/0000-0003-3701-8119)
- Ruirui Niu
- Xiangyan Han
- Zhi Gang Cheng (ORCID: https://orcid.org/0000-0002-9449-6734)
- Zheng Han (ORCID: https://orcid.org/0000-0001-5721-6206)
- Jianming Lü (ORCID: https://orcid.org/0000-0002-1558-4040)
- Zhuoxian Li
- Zhuangzhuang Qu
- Baojuan Dong (ORCID: https://orcid.org/0000-0002-6537-6047)
- Zhiyu Wang (ORCID: https://orcid.org/0000-0002-9757-7230)
- Yuting Zou (ORCID: https://orcid.org/0000-0003-0720-6645)
- Zizhao Gan
Institutions
- Shanxi University (CN)
- Chinese Academy of Sciences (CN)
- Peking University (CN)
- National Institute for Materials Science (JP)
- Hefei University (CN)
- Institute of Microelectronics (SG)
- Institute of Microelectronics (CN)
- FZU ‒ Institute of Physics of the Academy of Sciences of the Czech Republic (CZ)
- National Science Centre (PL)
- Liaoning Academy of Agricultural Sciences (CN)
- Shenyang Academy of Environmental Sciences (China) (CN)
- Institute of Physics (CN)
- University of Chinese Academy of Sciences (CN)
- State Key Laboratory of Quantum Optics and Quantum Optics Devices
Publication Details
- Journal
- Nature Communications
- Published
- 2024-11-11
- DOI
- https://doi.org/10.1038/s41467-024-54200-6
- Citations
- 2
- Primary Topic
- Graphene research and applications
- Type
- article
- Field-Weighted Citation Impact
- 0.23
Funders
- National Science Foundation
- National Natural Science Foundation of China
- Natural Science Foundation of Beijing Municipality