Title: Anisotropic susceptibilities in the honeycomb Kitaev system $\alpha -{\mathrm{RuCl}}_3$

Abstract

The magnetic insulator $\alpha -{\mathrm{RuCl}}_3$ is a promising candidate to realize Kitaev interactions on a quasi-two-dimensional honeycomb lattice. We perform extensive susceptibility measurements on single crystals of $\alpha -{\mathrm{RuCl}}_3$, including angle dependence of the in-plane longitudinal and transverse susceptibilities, which reveal a unidirectional anisotropy within the honeycomb plane. By comparing the experimental results to a high-temperature expansion of a Kitaev-Heisenberg-$$\textbf{Γ}$$ spin Hamiltonian with bond anisotropy, we find excellent agreement with the observed phase shift and periodicity of the angle-resolved susceptibilities. Within this model, we show that the pronounced difference between in-plane and out-of-plane susceptibilities as well as the finite transverse susceptibility are rooted in strong symmetric off-diagonal $$\textbf{Γ}$$ spin exchange. The $$\textbf{Γ}$$ couplings and relationships between other terms in the model Hamiltonian are quantified by extracting relevant Curie-Weiss intercepts from the experimental data.

Authors:

Lampen-Kelley, Paula J. ^[1]; Rachel, S. ^[2]; Reuther, J. ^[3]; Yan, Jiaqiang -Q.  ^[4];

• Search DOE PAGES for author "Yan, Jiaqiang -Q."
• Search DOE PAGES for ORCID "0000-0001-6625-4706"

Banerjee, Arnab  ^[5];

• Search DOE PAGES for author "Banerjee, Arnab"
• Search DOE PAGES for ORCID "0000-0002-3088-6071"

Bridges, Craig A.  ^[6];

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• Search DOE PAGES for ORCID "0000-0002-3543-463X"

Cao, Huibo B.  ^[5];

• Search DOE PAGES for author "Cao, Huibo B."
• Search DOE PAGES for ORCID "0000-0002-5970-4980"

Nagler, Stephen E.  ^[5];

• Search DOE PAGES for author "Nagler, Stephen E."
• Search DOE PAGES for ORCID "0000-0002-7234-2339"

Mandrus, D. ^[1]

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+ Show Author Affiliations

1. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
2. Univ. of Melbourne (Australia). School of Physics; Technical Univ. of Dresden (Germany). Inst. of Theoretical Physics
3. Freie Univ., Berlin (Germany). Dahlem Center for Complex Quantum Systems and Dept. of Physics; Helmholtz-Zentrum Berlin (HZB), (Germany). German Research Centre for Materials and Energy
4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Neutron Scattering Division
6. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division

Publication Date:

Wed Sep 12 00:00:00 EDT 2018

Research Org.:

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities Division; Gordon and Betty Moore Foundation; German Research Foundation (DFG)

OSTI Identifier:

1474459

Alternate Identifier(s):

OSTI ID: 1469737

Grant/Contract Number:  

AC05-00OR22725; GBMF4416; SFB 1143

Resource Type:

Accepted Manuscript

Journal Name:

Physical Review B

Additional Journal Information:

Journal Volume: 98; Journal Issue: 10; Journal ID: ISSN 2469-9950

Publisher:

American Physical Society (APS)

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; magnetic anisotropy; quantum spin liquid; DC susceptibility measurements; Kitaev-Heisenberg model