Spin dynamics in the Dirac $U(1)$ spin liquid YbZn$_2$GaO$_5$

Hank C. H. Wu; Francis L. Pratt; Benjamin M. Huddart; Dipranjan Chatterjee; Paul A. Goddard; John Singleton; D. Prabhakaran; Stephen J. Blundell

doi:10.1103/l93v-f576

arXiv · 2502.00130

Spin dynamics in the Dirac $U(1)$ spin liquid YbZn$_2$GaO$_5$

Hank C. H. Wu·Francis L. Pratt·Benjamin M. Huddart·Dipranjan Chatterjee·Paul A. Goddard·John Singleton·D. Prabhakaran·Stephen J. Blundell

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Abstract

YbZn$_2$GaO$_5$ is a promising candidate for realizing a quantum spin liquid (QSL) state, particularly owing to its lack of significant site disorder. Pulsed-field magnetometry at 0.5 K shows magnetization saturating near 15 T, with a corrected saturation moment of 2.1(1) $\mu_\mathrm{B}$ after subtracting the van Vleck contribution. Our zero-field $\mu$SR measurements down to milliKelvin temperatures provide evidence for a dynamic ground state and the absence of magnetic order. To probe fluctuations in the local magnetic field at the muon site, we performed longitudinal field $\mu$SR experiments. These results provide evidence for spin dynamics with a field dependence that is consistent with a U1A01 Dirac QSL as a plausible description of the ground state.

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Hank C. H. Wu, Francis L. Pratt, Benjamin M. Huddart, Dipranjan Chatterjee, Paul A. Goddard, John Singleton, D. Prabhakaran, Stephen J. Blundell. 2025-01-31. Spin dynamics in the Dirac $U(1)$ spin liquid YbZn$_2$GaO$_5$. https://doi.org/10.1103/l93v-f576

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