Rich nature of Van Hove singularities in Kagome superconductor CsV3Sb5

Abstract

Predictions suggest enhanced correlation effect due to multiple van Hove singularities (VHS) in the vicinity of the Fermi level in the recently discovered AV3Sb5 kagome metals. Here the authors identify three VHSs close to the Fermi level with diverse sublattice characters in CsV3Sb5, and one of them shows flat dispersion suggesting the higher-order nature.