Common Sublattice-Pure Van Hove Singularities in the Kagome Superconductors <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mi>A</mml:mi> <mml:msub> <mml:mi mathvariant="normal">V</mml:mi> <mml:mn>3</mml:mn>
Kagome materials offer a versatile platform for exploring correlated and topological quantum states, where Van Hove singularities (VHSs) play a pivotal role in driving electronic instabilities, exhibiting distinct behaviors depending on electron filling and interaction settings. In the recently discovered kagome superconductors AV_{3}Sb_{5} (A=K, Rb, Cs), unconventional charge density wave order, superconductivity, and electronic chirality emerge, yet the nature of VHSs near the Fermi level (E_{F}) and their connection to these exotic orders remain elusive. Here, using high-resolution polarization-dependent angle-resolved photoemission spectroscopy, we uncover a universal electronic structure across AV_{3}Sb_{5} that is distinct from density-functional theory predictions that show noticeable discrepancies. We identify multiple common sublattice-pure VHSs near E_{F}, arising from strong V-d/Sb-p hybridization, which significantly promote bond-order fluctuations and likely drive the observed charge density wave order. These findings provide direct spectroscopic evidence for hybridization-driven VHS formation in kagome metals and establish a unified framework for understanding the intertwined electronic instabilities in AV_{3}Sb_{5}.
Authors
- Karl J. Friston
Institutions
- University of California, Santa Barbara (US)
- Chongqing University (CN)
- Paul Scherrer Institute (CH)
- Hefei University (CN)
- Institute of Theoretical Physics (CN)
- Zhejiang University (CN)
Publication Details
- Journal
- Physical Review Letters
- Published
- 2025-12-04
- DOI
- https://doi.org/10.1103/njg9-jpkh
- Primary Topic
- Topological Materials and Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 0.00