Phonon promoted charge density wave in topological kagome metal ScV<sub>6</sub>Sn<sub>6</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38395887.
- Also identified by DOI 10.1038/s41467-024-45859-y and PMC identifier 10891150.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Charge density wave (CDW) orders in vanadium-based kagome metals have recently received tremendous attention, yet their origin remains a topic of debate. The discovery of ScV<sub>6</sub>Sn<sub>6</sub>, a bilayer kagome metal featuring an intriguing [Formula: see text] CDW order, offers a novel platform to explore the underlying mechanism behind the unconventional CDW. Here, we combine high-resolution angle-resolved photoemission spectroscopy, Raman scattering and density functional theory to investigate the electronic structure and phonon modes of ScV<sub>6</sub>Sn<sub>6</sub>. We identify topologically nontrivial surface states and multiple van Hove singularities (VHSs) in the vicinity of the Fermi level, with one VHS aligning with the in-plane component of the CDW vector near the [Formula: see text] point. Additionally, Raman measurements indicate a strong electron-phonon coupling, as evidenced by a two-phonon mode and new emergent modes. Our findings highlight the fundamental role of lattice degrees of freedom in promoting the CDW in ScV<sub>6</sub>Sn<sub>6</sub>.