We investigated the origins of charge density wave (CDW) mechanisms in the bi-layered kagome metal ScV6Sn6 by comparing its electronic structure with that of its isostructural counterpart YV6Sn6, which does not exhibit a CDW state. Our ARPES measurements reveal that the Van Hove singularity (VHS) nesting mechanism may not be valid in the CDW state. In ScV6Sn6, the electronic structure shows a CDW-induced band gap accompanied by anomalous band dispersion near the M point of the Brillouin zone. These findings provide experimental evidence for the origin of CDW in vanadium-based kagome metals.
- Yi-Chen Yang
- Soohyun Cho
- Da-Wei Shen