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arXiv · 1802.10060

Detuning the Honeycomb of $\alpha$-RuCl$_{3}$: Pressure-Dependent Optical Studies Reveal Broken Symmetry

Tobias Biesner·Sananda Biswas·Weiwu Li·Yohei Saito·Andrej Pustogow·Michaela Altmeyer·Anja U. B. Wolter·Bernd Büchner·Maria Roslova·Thomas Doert·Stephen M. Winter·Roser Valentí·Martin Dressel
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Abstract

The honeycomb Mott insulator $\alpha$-RuCl$_3$ loses its low-temperature magnetic order by pressure. We report clear evidence for a dimerized structure at $P>1$ GPa and observe the breakdown of the relativistic $j_{\rm eff}$ picture in this regime strongly affecting the electronic properties. A pressure-induced Kitaev quantum spin liquid cannot occur in this broken symmetry state. We shed light on the new phase by broad-band infrared spectroscopy of the low-temperature properties of $\alpha$-RuCl$_{3}$ and ab initio density functional theory calculations, both under hydrostatic pressure.

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Tobias Biesner, Sananda Biswas, Weiwu Li, Yohei Saito, Andrej Pustogow, Michaela Altmeyer, Anja U. B. Wolter, Bernd Büchner, Maria Roslova, Thomas Doert, Stephen M. Winter, Roser Valentí, Martin Dressel. 2018-02-27. Detuning the Honeycomb of $\alpha$-RuCl$_{3}$: Pressure-Dependent Optical Studies Reveal Broken Symmetry. https://doi.org/10.1103/physrevb.97.220401

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