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  • Letter
  • Open Access

Exceptional dynamics of interacting spin liquids

Kang Yang1, Daniel Varjas1, Emil J. Bergholtz1, Sid Morampudi2, and Frank Wilczek1,2,3,4,5

  • 1Department of Physics, Stockholm University, AlbaNova University Center, 106 91 Stockholm, Sweden
  • 2Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
  • 3T. D. Lee Institute, Shanghai 201210, China
  • 4Wilczek Quantum Center, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
  • 5Department of Physics and Origins Project, Arizona State University, Tempe, Arizona 25287, USA

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Phys. Rev. Research 4, L042025 – Published 14 November, 2022

DOI: https://doi.org/10.1103/PhysRevResearch.4.L042025

Abstract

We show that interactions in quantum spin liquids can result in non-Hermitian phenomenology that differs qualitatively from mean-field expectations. We demonstrate this in two prominent cases through the effects of phonons and disorder on a Kitaev honeycomb model. Using analytic and numerical calculations, we show the generic appearance of exceptional points and rings depending on the symmetry of the system. Their existence is reflected in dynamical observables including the dynamic structure function measured in neutron scattering. The results point to different phenomenological features in realizable spin liquids that must be incorporated into the analysis of experimental data and also indicate that spin liquids could be generically stable to wider classes of perturbations.

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Phys. Rev. Research 4, L042025– Published 14 November, 2022
  • Received 14 February 2022
  • Accepted 29 September 2022
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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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