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arXiv · 2407.12099

Frustrated Ising charge correlations in the kagome metal ScV$_6$Sn$_6$

S. J. Gomez Alvarado·G. Pokharel·B. R. Ortiz·Joseph A. M. Paddison·Suchismita Sarker·J. P. C. Ruff·Stephen D. Wilson
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Abstract

Here we resolve the real-space nature of the high-temperature, short-range charge correlations in the kagome metal ScV$_6$Sn$_6$. Diffuse scattering appears along a frustrated wave vector $\textbf{q}_H=(\frac{1}{3},\frac{1}{3},\frac{1}{2})$ at temperatures far exceeding the charge order transition $T_{CO}=92~\mathrm{K}$, preempting long-range charge order with wave vectors along $\textbf{q}_{\bar{K}}=(\frac{1}{3},\frac{1}{3},\frac{1}{3})$. Using a combination of real space and reciprocal space analysis, we resolve the nature of the interactions between the primary out-of-plane Sc-Sn chain instability and the secondary strain-mediated distortion of the in-plane V kagome network. A minimal model of the diffuse scattering data reveals a high-temperature, short-ranged "zig-zag" phase of in-plane correlations that maps to a frustrated triangular lattice Ising model with antiferromagnetic interactions and provides a real-space understanding of the origin of frustrated charge order in this material.

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S. J. Gomez Alvarado, G. Pokharel, B. R. Ortiz, Joseph A. M. Paddison, Suchismita Sarker, J. P. C. Ruff, Stephen D. Wilson. 2024-07-16. Frustrated Ising charge correlations in the kagome metal ScV$_6$Sn$_6$. https://doi.org/10.1103/physrevb.110.l140304

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