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Z2q parafermionic hinge states in a three-dimensional array of coupled nanowires

Sarthak Girdhar*, Viktoriia Pinchenkova, Even Thingstad, and Jelena Klinovaja

  • *Contact author: sarthak.sarthak@unibas.ch
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Phys. Rev. Research 8, 033257 – Published 1 September, 2026

DOI: https://doi.org/10.1103/4jdx-k37q

Abstract

We construct a model of a three-dimensional helical second-order topological superconductor formed by an array of weakly coupled Rashba nanowires. We identify the parameter regime in which there are energy gaps in both the bulk and surface energy spectra, while a pair of helical Z2q parafermionic modes (with q being an odd integer) remains gapless along a closed path of one-dimensional hinges. The precise trajectory of these hinge modes is dictated by the hierarchy of interwire couplings and the boundary termination of the sample. In the noninteracting limit q=1, the system hosts gapless Majorana hinge modes.

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Phys. Rev. Research 8, 033257– Published 1 September, 2026
  • Received 10 April 2026
  • Accepted 8 August 2026
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