Observation of Fermi-surface-dependent anisotropic Cooper pairing in kagome superconductor CsV3Sb5
Abstract In the recently discovered kagome superconductor A V 3 Sb 5 ( A = K, Rb, and Cs), superconductivity is intertwined with an unconventional charge density wave order. The pairing symmetry remains elusive owing to the lack of direct measurement of the superconducting gap in the momentum space. Here, utilizing laser-based ultra-high-resolution and low-temperature angle-resolved photoemission spectroscopy, we observe Fermi-surface-dependent anisotropic Cooper pairing in kagome superconductor CsV 3 Sb 5 . We detect a highly anisotropic superconducting gap structure with anisotropy exceeding 80% and a gap maximum along the V-V bond direction on a Fermi surface originating from the 3 d -orbital electrons of the V kagome lattice. This is in stark contrast to the isotropic superconducting gap structure on the Fermi surface occupied by Sb 5 p -orbital electrons. Our direct observation of the Fermi-surface-dependent anisotropic pairing in CsV 3 Sb 5 is fundamental for understanding the intertwined orders in the ground state of kagome superconductors.
Authors
- Jia‐Xin Yin (ORCID: https://orcid.org/0000-0003-2661-4206)
- Takeshi Suzuki (ORCID: https://orcid.org/0000-0003-1261-7131)
- Sahand Najafzadeh
- Kozo Okazaki (ORCID: https://orcid.org/0000-0002-2334-918X)
- Akifumi Mine (ORCID: https://orcid.org/0000-0001-6688-6340)
- Xianxin Wu (ORCID: https://orcid.org/0009-0004-3916-7120)
- Yigui Zhong (ORCID: https://orcid.org/0000-0003-4613-359X)
- Yugui Yao (ORCID: https://orcid.org/0000-0003-3544-3787)
- Takumi Uchiyama
- Zhiwei Wang (ORCID: https://orcid.org/0000-0003-0182-2471)
- Jinjin Liu (ORCID: https://orcid.org/0000-0001-7391-8873)
- Xun Shi (ORCID: https://orcid.org/0000-0001-8719-911X)
Institutions
- Beijing Institute of Technology (CN)
- Southern University of Science and Technology (CN)
- Ube Frontier University (JP)
- Beijing Institute of Optoelectronic Technology (CN)
- Institute of Theoretical Physics (CN)
- The University of Tokyo (JP)
- The University of Osaka (JP)
Publication Details
- Journal
- Communications Materials
- Published
- 2025-11-28
- DOI
- https://doi.org/10.1038/s43246-025-01002-y
- Citations
- 1
- Primary Topic
- Topological Materials and Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 1.25
Funders
- Ministry of Education, Culture, Sports, Science and Technology
- National Natural Science Foundation of China
- Beijing Institute of Technology
- South University of Science and Technology of China
- University of Science and Technology of China
- Japan Society for the Promotion of Science
- Japan Science and Technology Agency
- National Key Research and Development Program of China
- Center of Innovation Program