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  • Letter
  • Open Access

Static impurity in a mesoscopic system of SU(N) fermionic matter waves

Juan Polo1,*, Wayne J. Chetcuti1,2, Anna Minguzzi2, Andreas Osterloh1, and Luigi Amico1,3,4

  • *Contact author: juan.polo@tii.ae
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Phys. Rev. Research 8, L022015 – Published 15 April, 2026

DOI: https://doi.org/10.1103/tcmp-nf52

Abstract

We investigate the effects of a static impurity, modeled by a localized barrier, in a one-dimensional mesoscopic system comprised of strongly correlated repulsive SU(N)-symmetric fermions. For a mesoscopic sized ring under the effect of an artificial gauge field, we analyze the energy spectrum, the particle density, and the current flowing through the impurity at varying interaction strengths, barrier heights, and number of components. We find that the physics of the system is governed by the competition between effective single-particle process and the formation of a high-stiffness spin-correlated state associated with the phenomenon of fractionalization of the flux quantum characterizing the N-component fermionic system. Our findings provide a route to probe the response of SU(N) fermions to effective magnetic fields; at the same time, they hold significance for fundamental understanding of localized impurity problems.

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Phys. Rev. Research 8, L022015– Published 15 April, 2026
  • Received 28 November 2024
  • Revised 9 June 2025
  • Accepted 23 February 2026
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