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arXiv · 2103.14045

Analysis of Charge Order in the Kagome Metal $A$V$_3$Sb$_5$ ($A=$K,Rb,Cs)

M. Michael Denner·Ronny Thomale·Titus Neupert
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Abstract

Motivated by the recent discovery of unconventional charge order, we develop a theory of electronically mediated charge density wave formation in the family of kagome metals $A$V$_3$Sb$_5$ ($A=$K,Rb,Cs). The intertwining of van Hove filling and sublattice interference suggests a three-fold charge density wave instability at T$_{\text{CDW}}$. From there, the charge order forming below T$_{\text{CDW}}$ can unfold into a variety of phases capable of exhibiting orbital currents and nematicity. We develop a Ginzburg Landau formalism to stake out the parameter space of kagome charge order. We find a nematic chiral charge order to be energetically preferred, which shows tentative agreement with experimental evidence.

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M. Michael Denner, Ronny Thomale, Titus Neupert. 2021-03-25. Analysis of Charge Order in the Kagome Metal $A$V$_3$Sb$_5$ ($A=$K,Rb,Cs). https://doi.org/10.1103/physrevlett.127.217601

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