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Zeeman ladders in frustrated XYZ spin chains

Catalin-Mihai Halati1,2, Viola Romerio3, Paul Steffens4, J. Ross Stewart5, Andrey Zheludev3, and Thierry Giamarchi2,*

  • *Contact author: Thierry.Giamarchi@unige.ch
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Phys. Rev. Research 8, 033206 – Published 18 August, 2026

DOI: https://doi.org/10.1103/7pzn-3ygf

Abstract

We investigate the nature of the excitations captured by the dynamical response of XYZ triangular spin-1/2 ladders. We complement experimental inelastic neutron scattering results on the compound Cs2CoBr4 with numerically exact simulations based on time-dependent matrix product state methods. Our results show that bound states of spinon excitations can arise in XYZ beyond the requirement of strong Ising anisotropies. We analyze the role of the frustrated triangular couplings on the excitations giving rise to the spin dynamical structure factor and show how the features of the bound states manifest themselves in the different polarization channels.

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Phys. Rev. Research 8, 033206– Published 18 August, 2026
  • Received 25 August 2025
  • Revised 4 June 2026
  • Accepted 29 July 2026
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