English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

In a new family of V-based kagome metals RV$_6$Sn$_6$ (R = Sc, Y, La), onlyScV$_6$Sn$_6$ was observed to exhibit the unusual charge density wave (CDW)with a $\sqrt{3}{\times}\sqrt{3}$ in-plane ordering and a tripling of the unitcell along the $c$-axis. However, the driving mechanism of such a$\sqrt{3}{\times}\sqrt{3}{\times}$3 CDW order is elusive. Here, usingfirst-principles density-functional theory calculations, we demonstrate thatthe $\sqrt{3}{\times}\sqrt{3}{\times}$2 or $\sqrt{3}{\times}\sqrt{3}{\times}$3CDW order is driven by a Jahn-Teller-like effect where the interlayerdimerization of Sn atoms in kagome bilayers is accompanied by a chargeredistribution between such Sn atoms and its associated gap opening. It isrevealed that the free energy of the $\sqrt{3}{\times}\sqrt{3}{\times}$3 phasebecomes lower than that of the $\sqrt{3}{\times}\sqrt{3}{\times}$2 phase above$T_{\rm CDW}$ mostly due to the emergence of a large configurational entropy.Such a high-entropy phase shows dynamic fluctuations between its degenerateconfigurations but, as the temperature lowers below $T_{\rm CDW}$, it can bekinetically trapped to release a sizable entropy. Our findings not onlyidentify the driving mechanism and order-disorder transition of the CDW inScV$_6$Sn$_6$ but also provide an ideal platform for investigating strong CDWfluctuations in V-based kagome metals.

Driving Mechanism and Dynamic Fluctuations of Charge Density Waves in the Kagome Metal ScV$_6$Sn$_6$