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Low-temperature spin dynamics and absence of magnetic order in layered α−RuI3

Hank C. H. Wu1,*, Benjamin M. Huddart1, Francis L. Pratt2, Danrui Ni3, Robert J. Cava3, and Stephen J. Blundell1,†

  • 1Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
  • 2ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX, United Kingdom
  • 3Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States

  • *Contact author: hank.wu@physics.ox.ac.uk
  • †Contact author: stephen.blundell@physics.ox.ac.uk
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Phys. Rev. B 114, 014411 – Published 10 July, 2026

DOI: https://doi.org/10.1103/kxbj-gp8z

Abstract

The honeycomb-lattice system α−RuI3 is isostructural to the widely studied α−RuCl3 compound which was identified as a potential Kitaev system but exhibits, instead of spin liquid behavior, a magnetically ordered zigzag ground state which sets in below 14 K. Here we show experimentally that, in contrast, the spins in α−RuI3 remain dynamic down to at least 50 mK. We study the spin dynamics using muon-spin relaxation methods and determine the presence of low-frequency fluctuations which are characteristic of a two-dimensional system.

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Outline

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Phys. Rev. B 114, 014411– Published 10 July, 2026
  • Received 6 June 2024
  • Revised 9 March 2026
  • Accepted 11 June 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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