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arXiv · 2504.20871

Fluctuating magnetism in Zn-doped averievite with well-separated kagome layers

G. Simutis·L. Suárez-García·H. Zeroual·I. Villa·M. Georgopoulou·D. Boldrin·C. N. Wang·C. Baines·T. Shiroka·R. Khasanov·H. Luetkens·B. Fåk·Y. Sassa·M. Bartkowiak·A. S. Wills·E. Kermarrec·F. Bert·P. Mendels
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Abstract

Kagome lattice decorated with S=1/2 spins is one of the most discussed ways to realize a quantum spin liquid. However, all previous material realizations of this model have suffered from additional complications, ranging from additional interactions to impurity effects. Recently, a new quantum kagome system has been identified in the form of averievite Cu(5-x)ZnxV2O10(CsCl), featuring a unique double-layer spacing between the kagome planes. Using muon spin spectroscopy we show that only a complete substitution (i.e. $x=2$) of interplanar copper ions leads to a quantum-disordered ground state. In contrast, the parent compound ($x=0$) exhibits long-range magnetic order, with a phase transition around 24 K. Experiments performed on the partially substituted material ($x=1$) show that the transformation proceeds through an intermediate disordered, partially frozen ground state, unaffected by pressures up to 23 kbar. Our study provides a microscopic view of the magnetism of the decoupling of the kagome layers and establishes the averievite as a new material platform for the experimental study of the fully-decoupled kagome layers.

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G. Simutis, L. Suárez-García, H. Zeroual, I. Villa, M. Georgopoulou, D. Boldrin, C. N. Wang, C. Baines, T. Shiroka, R. Khasanov, H. Luetkens, B. Fåk, Y. Sassa, M. Bartkowiak, A. S. Wills, E. Kermarrec, F. Bert, P. Mendels. 2025-04-29. Fluctuating magnetism in Zn-doped averievite with well-separated kagome layers. https://doi.org/10.1103/l7gq-cc96

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