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arXiv · 2012.15258

Field-induced intermediate ordered phase and anisotropic interlayer interactions in $\alpha$-RuCl$_3$

Christian Balz·Lukas Janssen·Paula Lampen-Kelley·Arnab Banerjee·Yaohua Liu·Jiaqiang Yan·David Mandrus·Matthias Vojta·Stephen E. Nagler
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Abstract

In $\alpha$-RuCl$_3$, an external magnetic field applied within the honeycomb plane can induce a transition from a magnetically ordered state to a disordered state that is potentially related to the Kitaev quantum spin liquid. In zero field, single crystals with minimal stacking faults display a low-temperature state with in-plane zigzag antiferromagnetic order and a three-layer periodicity in the direction perpendicular to the honeycomb planes. Here, we present angle-dependent magnetization, ac susceptibility, and thermal transport data that demonstrate the presence of an additional intermediate-field ordered state at fields below the transition to the disordered phase. Neutron diffraction results show that the magnetic structure in this phase is characterized by a six-layer periodicity in the direction perpendicular to the honeycomb planes. Theoretically, the intermediate ordered phase can be accounted for by including spin-anisotropic couplings between the layers in a three-dimensional spin model. Together, this demonstrates the importance of interlayer exchange interactions in $\alpha$-RuCl$_3$.

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Christian Balz, Lukas Janssen, Paula Lampen-Kelley, Arnab Banerjee, Yaohua Liu, Jiaqiang Yan, David Mandrus, Matthias Vojta, Stephen E. Nagler. 2020-12-30. Field-induced intermediate ordered phase and anisotropic interlayer interactions in $\alpha$-RuCl$_3$. https://doi.org/10.1103/physrevb.103.174417

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