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Observation of a topological phase transition in random coaxial cable structures with chiral symmetry

D. M. Whittaker

Maxine M. McCarthy

Qingqing Duan

  • Physics and Astronomy, School of Mathematical and Physical Sciences, University of Sheffield, Sheffield S3 7RH, United Kingdom

  • Physics and Astronomy, School of Mathematical and Physical Sciences, University of Sheffield, Sheffield S3 7RH, United Kingdom and Max Planck Institute for the Science of Light, Staudstraße 2, 91058 Erlangen, Germany

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Phys. Rev. B 114, 144203 – Published 16 September, 2026

DOI: https://doi.org/10.1103/hnqs-xh69

Abstract

We report an experimental study of the disordered Su-Schrieffer-Heeger (SSH) model, implemented in a system of coaxial cables, whose radio frequency properties map onto the SSH Hamiltonian. By measuring multiple chains with random hopping terms, we demonstrate the presence of a topologically protected state, with frequency variation of less than 0.2% over the ensemble, evidence of near-perfect chiral symmetry. When the ends of the chains are connected to form loops, we observe a topological phase transition, characterized by the closure of the band gap and the appearance of states that are delocalized, despite the strong disorder.

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References (34)

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Phys. Rev. B 114, 144203– Published 16 September, 2026
  • Received 17 June 2024
  • Revised 26 June 2026
  • Accepted 12 August 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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