Origin of competing charge density waves in kagome metal ScV₆Sn₆.

ABSTRACT: Understanding competing charge density wave (CDW) orders in the bilayer kagome metal ScV6Sn6 remains challenging. Experimentally, upon cooling, short-range order with wave vector q2=(13,13,12) forms, which is subsequently suppressed by the condensation of long-range q3=(13,13,13) CDW order at lower temperature. Theoretically, however, the q2 CDW is predicted as the ground state, leaving the CDW mechanism elusive. Here, using anharmonic phonon-phonon calculations combined with density functional theory, we predict a temperature-driven structural phase transitions from the high-temperature pristine phase to the q2 CDW, followed by the low-temperature q3 CDW, explaining experimental observations. We demonstrate that semi-core electron states stabilize the q3 CDW over the q2 CDW. Furthermore,

SUBMITTER: Wang K 

PROVIDER: S-EPMC11608277 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature