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(2+1)D quantum electrodynamics at finite density on a quantum computer

Emil Otis Rosanowski1,*, Arianna Crippa2, Lena Funcke1, Paulo Vitor Itaboraí3,2, Karl Jansen3,2, and Simran Singh1

  • 1Transdisciplinary Research Area “Building Blocks of Matter and Fundamental Interactions” (TRA Matter) and Helmholtz Institute for Radiation and Nuclear Physics (HISKP), University of Bonn, Nussallee 14-16, 53115 Bonn, Germany
  • 2Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, 15738 Zeuthen, Germany
  • 3Computation-Based Science and Technology Research Center, The Cyprus Institute, 20 Kavafi Street, 2121 Nicosia, Cyprus

  • *Contact author: rosanowski@hiskp.uni-bonn.de
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Phys. Rev. D 114, 014501 – Published 1 July, 2026

DOI: https://doi.org/10.1103/3ntp-l3s7

Abstract

In this paper, we explore (2+1)D quantum electrodynamics at finite density on a quantum computer, including two fermion flavors. Our method employs an established gauge-invariant Ansatz together with a quantum circuit structure that enforces Gauss’s law. As a proof of principle, we benchmark our simulation protocol on a small lattice system of 2×2, demonstrating the identification of density-induced level crossings in terms of the particle number of the fermion flavors. Classical simulations are used to obtain optimized variational parameters, which are then deployed in inference runs on IBM quantum hardware. We conclude by discussing hardware limitations and prospects for scaling this method to larger systems.

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Phys. Rev. D 114, 014501– Published 1 July, 2026
  • Received 2 October 2025
  • Accepted 27 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. Funded by SCOAP3.

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