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  • Letter
  • Open Access

Gapless edge gravitons and quasiparticles in fractional quantum Hall systems with nonlocal confinement

Daniel Spasic-Mlacak* and Nigel R. Cooper

  • *Contact author: ds2069@cam.ac.uk
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Phys. Rev. Research 8, L022063 – Published 29 June, 2026

DOI: https://doi.org/10.1103/2m3h-7x3r

Abstract

One of the central tenets of the theory of the fractional quantum Hall effect is that the bulk quantized Hall response requires the existence of a gapless chiral edge mode. The field-theoretical arguments for this rely on locality. While locality is typically met in standard experimental settings, it need not always apply. Motivated by experimental capabilities of photonic platforms, we study confining potentials that are steplike in angular momentum, and thus nonlocal in position. We show that this nonlocal potential does not host conventional chiral edge modes. These are replaced by gapless spin-2 edge states, which we show are connected to the collective “graviton” excitations that are gapped in the bulk. Furthermore, we show that fractional quantum Hall states host gapless (charged) quasiparticles on their edges, even in the absence of conventional edge modes. The edge state energies vanish as a power law in system size, with an exponent that characterizes the bulk topological order.

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Phys. Rev. Research 8, L022063– Published 29 June, 2026
  • Received 25 August 2025
  • Accepted 11 May 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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