Electron correlation and incipient flat bands in the Kagome superconductor CsCr3Sb5
Correlated kagome materials exhibit a compelling interplay between lattice geometry, electron correlation, and topology. In particular, the flat bands near the Fermi level provide a fertile playground for novel many-body states. Here we investigate the electronic structure of CsCr<sub>3</sub>Sb<sub>5</sub> using high-resolution angle-resolved photoemission spectroscopy and ab-initio calculations. Our results suggest that Cr 3d electrons are intrinsically incoherent, showing strong electron correlation amplified by Hund's coupling. Notably, we identify incipient flat bands close to the Fermi level, which are expected to significantly influence the electronic properties of the system. Across the density-wave-like transition at 55 K, we observe a drastic enhancement of the electron scattering rate, which aligns with the semiconducting-like property at high temperatures. These findings establish CsCr<sub>3</sub>Sb<sub>5</sub> as a strongly correlated Hund's metal with incipient flat bands near the Fermi level, which provides an electronic basis for understanding its novel properties compared to the weakly correlated AV<sub>3</sub>Sb<sub>5</sub>.
Authors
- Houke Chen (ORCID: https://orcid.org/0000-0002-0261-7480)
- Guang‐Han Cao (ORCID: https://orcid.org/0000-0002-9669-5761)
- Jieyi Liu (ORCID: https://orcid.org/0000-0001-6588-5987)
- Yidian Li (ORCID: https://orcid.org/0009-0004-2189-109X)
- Yiheng Yang (ORCID: https://orcid.org/0000-0003-1840-2748)
- Dong-Hui Lu (ORCID: https://orcid.org/0000-0002-9708-0443)
- Zhongkai Liu (ORCID: https://orcid.org/0000-0003-3373-8039)
- Xian Du
- Wenxuan Zhao (ORCID: https://orcid.org/0000-0003-4444-3674)
- Makoto Hashimoto (ORCID: https://orcid.org/0000-0003-1689-8997)
- Yilin Wang (ORCID: https://orcid.org/0000-0002-3386-5380)
- Lexian Yang (ORCID: https://orcid.org/0000-0002-0078-1797)
- Yulin Chen (ORCID: https://orcid.org/0000-0001-8960-9725)
- Yi Liu (ORCID: https://orcid.org/0000-0002-6735-831X)
- Cheng Peng (ORCID: https://orcid.org/0009-0006-3433-1467)
- Siqi Wu (ORCID: https://orcid.org/0000-0001-8156-5596)
- Yinqi Hu (ORCID: https://orcid.org/0009-0005-6277-6327)
- Senyao Zhang
- Kaiyi Zhai
Institutions
- University of Science and Technology of China (CN)
- Hefei University of Technology (CN)
- SLAC National Accelerator Laboratory (US)
- ShanghaiTech University (CN)
- University of Oxford (GB)
- Stanford Synchrotron Radiation Lightsource (US)
- Collaborative Innovation Center of Quantum Matter (CN)
- Zhejiang University of Technology (CN)
- Zhejiang University (CN)
- Tsinghua University (CN)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-04-04
- DOI
- https://doi.org/10.1038/s41467-025-58487-x
- Citations
- 16
- Primary Topic
- Advanced Condensed Matter Physics
- Type
- article
- Field-Weighted Citation Impact
- 20.13
Funders
- U.S. Department of Energy
- Salt Science Research Foundation
- National Natural Science Foundation of China
- Ministry of Science and Technology of the People's Republic of China
- Office of Science
- Science and Technology on Surface Physics and Chemistry Laboratory
- Basic Energy Sciences
- SLAC National Accelerator Laboratory