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arXiv · 1902.07749

Persistent spin dynamics in the pressurized spin-liquid candidate YbMgGaO$_4$

Mayukh Majumder·Gediminas Simutis·Ines E. Collings·Jean-Christophe Orain·Tusharkanti Dey·Yuesheng Li·Philipp Gegenwart·Alexander A. Tsirlin
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Abstract

Single-crystal x-ray diffraction, density-functional band-structure calculations, and muon spin relaxation ($\mu$SR) are used to probe pressure evolution of the triangular spin-liquid candidate YbMgGaO$_4$. The rhombohedral crystal structure is retained up to at least 10 GPa and shows a nearly uniform compression along both in-plane and out-of-plane directions, whereas local distortions caused by the random distribution of Mg$^{2+}$ and Ga$^{3+}$ remain mostly unchanged. The $\mu$SR data confirm persistent spin dynamics up to 2.6 GPa and down to 250 mK with no change in the muon relaxation rate. Longitudinal-field $\mu$SR reveals power-law behavior of the spin-spin autocorrelation function, both at ambient pressure and upon compression.

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Mayukh Majumder, Gediminas Simutis, Ines E. Collings, Jean-Christophe Orain, Tusharkanti Dey, Yuesheng Li, Philipp Gegenwart, Alexander A. Tsirlin. 2019-02-20. Persistent spin dynamics in the pressurized spin-liquid candidate YbMgGaO$_4$. https://doi.org/10.1103/physrevresearch.2.023191

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