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arXiv · 2307.11843

Frustrated charge order and cooperative distortions in ScV6Sn6

Ganesh Pokharel·Brenden R. Ortiz·Linus Kautzsch·S. J. Gomez Alvarado·Krishnanand Mallayya·Guang Wu·Eun-Ah Kim·Jacob P. C. Ruff·Suchismita Sarker·Stephen D. Wilson
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Abstract

Here we study the stability of charge order in the kagome metal ScV6Sn6. Synchrotron x-ray diffraction measurements reveal high-temperature, short-range charge correlations at the wave vectors along q=(1/3,1/3,1/2) whose inter-layer correlation lengths diverge upon cooling. At the charge order transition, this divergence is interrupted and long-range order freezes in along q=(1/3,1/3,1/3), as previously reported, while disorder enables the charge correlations to persist at the q=(1/3,1/3,1/2) wave vector down to the lowest temperatures measured. Both short-range and long-range charge correlations seemingly arise from the same instability and both are rapidly quenched upon the introduction of larger Y ions onto the Sc sites. Our results validate the theoretical prediction of the primary lattice instability at q=(1/3,1/3,1/2), and we present a heuristic picture for viewing the frustration of charge order in this compound.

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Ganesh Pokharel, Brenden R. Ortiz, Linus Kautzsch, S. J. Gomez Alvarado, Krishnanand Mallayya, Guang Wu, Eun-Ah Kim, Jacob P. C. Ruff, Suchismita Sarker, Stephen D. Wilson. 2023-07-21. Frustrated charge order and cooperative distortions in ScV6Sn6. https://doi.org/10.1103/physrevmaterials.7.104201

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