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arXiv · 2503.04656

Spin-strain interactions under hydrostatic pressure in $\alpha$-RuCl$_3$

A. Hauspurg·Susmita Singh·T. Yanagisawa·V. Tsurkan·J. Wosnitza·Wolfram Brenig·Natalia B. Perkins·S. Zherlitsyn
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Abstract

We investigate the effects of hydrostatic pressure on $\alpha$-RuCl$_3$, a prototypical material for the Kitaev spin model on a honeycomb lattice with a possible spin-liquid ground state. Using ultrasound measurements at pressures up to 1.16 GPa, we reveal significant modifications of the acoustic properties and the $H$-$T$ phase diagram of this material. Hydrostatic pressure suppresses the three-dimensional magnetic order and induces a dimerization transition at higher pressures. At low pressures, the sound attenuation exhibits a linear temperature dependence, while above 0.28 GPa, it becomes nearly temperature independent, suggesting a shift in the phonon scattering regime dominated by Majorana fermions. These findings provide new insights into spin-strain interactions in Kitaev magnets and deliver a detailed characterization of the $H$-$T$ phase diagram of $\alpha$-RuCl$_3$ under hydrostatic pressure.

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A. Hauspurg, Susmita Singh, T. Yanagisawa, V. Tsurkan, J. Wosnitza, Wolfram Brenig, Natalia B. Perkins, S. Zherlitsyn. 2025-03-06. Spin-strain interactions under hydrostatic pressure in $\alpha$-RuCl$_3$. https://arxiv.org/abs/2503.04656

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