- Open Access
Precision study of the massive Schwinger model near quantum criticality
Phys. Rev. D 112, 034023 – Published 22 August, 2025
DOI: https://doi.org/10.1103/vf7m-kzk2
Abstract
We perform a numerical analysis of the massive Schwinger model in the presence of a background electric field. Using the Density Matrix Renormalization Group approach, we efficiently compute the spectrum of the Schwinger model on a staggered lattice with up to 3000 qubits. As a result, we achieve a precise computation of the critical mass of the massive Schwinger model to five digits using four different “criticality criteria,” observing perfect agreement among them Additionally, we discuss the effect of a four-fermion operator deformation of the Schwinger model and compute the critical mass for various values of the deformation parameter.
Physics Subject Headings (PhySH)
Article Text
References (64)
- J. S. Schwinger, Gauge invariance and mass. 2., Phys. Rev. 128, 2425 (1962).
- J. H. Lowenstein and J. A. Swieca, Quantum electrodynamics in two-dimensions, Ann. Phys. (N.Y.) 68, 172 (1971).
- A. Casher, J. Kogut, and L. Susskind, Vacuum polarization and the absence of free quarks, Phys. Rev. D 10, 732 (1974).
- S. R. Coleman, R. Jackiw, and L. Susskind, Charge shielding and quark confinement in the massive Schwinger model, Ann. Phys. (N.Y.) 93, 267 (1975).
- S. R. Coleman, More about the massive Schwinger model, Ann. Phys. (N.Y.) 101, 239 (1976).
- M. Creutz, One flavor QCD, Ann. Phys. (N.Y.) 322, 1518 (2007).
- T. Byrnes, P. Sriganesh, R. J. Bursill, and C. J. Hamer, Density matrix renormalization group approach to the massive Schwinger model, Nucl. Phys. B, Proc. Suppl. 109, 202 (2002).
- T. Byrnes, Density Matrix Renormalization Group: A New Approach to Lattice Gauge Theory, Ph.D. thesis, University of New South Wales, 2003.
- B. Buyens, S. Montangero, J. Haegeman, F. Verstraete, and K. Van Acoleyen, Finite-representation approximation of lattice gauge theories at the continuum limit with tensor networks, Phys. Rev. D 95, 094509 (2017).
- H. Ohata, Phase diagram near the quantum critical point in Schwinger model at : Analogy with quantum Ising chain, Prog. Theor. Exp. Phys. 2024, 013B02 (2024).
- R. Dempsey, I. R. Klebanov, S. S. Pufu, B. T. Søgaard, and B. Zan, Phase diagram of the two-flavor Schwinger model at zero temperature, Phys. Rev. Lett. 132, 031603 (2024).
- H. Fujii, K. Fujikura, Y. Kikukawa, T. Okuda, and J. W. Pedersen, Critical behavior of the Schwinger model via gauge-invariant variational uniform matrix product states, Phys. Rev. D 111, 094505 (2025).
- R. Dempsey, I. R. Klebanov, S. S. Pufu, and B. Zan, Discrete chiral symmetry and mass shift in the lattice Hamiltonian approach to the Schwinger model, Phys. Rev. Res. 4, 043133 (2022).
- J. Ranft and A. Schiller, Local Hamiltonian Monte Carlo study of the massive Schwinger model in an external background field, Phys. Lett. 122B, 403 (1983).
- A. Schiller and J. Ranft, The massive Schwinger model on the lattice studied via a local Hamiltonian Monte Carlo method, Nucl. Phys. B225, 204 (1983).
- H. Ohata, Monte Carlo study of Schwinger model without the sign problem, J. High Energy Phys. 12 (2023) 007.
- S. R. White, Density matrix formulation for quantum renormalization groups, Phys. Rev. Lett. 69, 2863 (1992).
- S. R. White, Density-matrix algorithms for quantum renormalization groups, Phys. Rev. B 48, 10345 (1993).
- S. Östlund and S. Rommer, Thermodynamic limit of density matrix renormalization, Phys. Rev. Lett. 75, 3537 (1995).
- G. Vidal, Classical simulation of infinite-size quantum lattice systems in one spatial dimension, Phys. Rev. Lett. 98, 070201 (2007).
- I. P. McCulloch, Infinite size density matrix renormalization group, revisited, arXiv:0804.2509.
- Y. Zou, A. Milsted, and G. Vidal, Conformal data and renormalization group flow in critical quantum spin chains using periodic uniform matrix product states, Phys. Rev. Lett. 121, 230402 (2018).
- M. Ganahl, J. Rincón, and G. Vidal, Continuous matrix product states for quantum fields: An energy minimization algorithm, Phys. Rev. Lett. 118, 220402 (2017).
- M. C. Bañuls, K. Cichy, K. Jansen, and J. I. Cirac, The mass spectrum of the Schwinger model with matrix product states, J. High Energy Phys. 11 (2013) 158.
- M. C. Bañuls, K. Cichy, J. I. Cirac, K. Jansen, and H. Saito, Matrix product states for lattice field theories, Proc. Sci., LATTICE2013 (2014) 332.
- Y. Shimizu and Y. Kuramashi, Critical behavior of the lattice Schwinger model with a topological term at using the Grassmann tensor renormalization group, Phys. Rev. D 90, 074503 (2014).
- B. Buyens, J. Haegeman, K. Van Acoleyen, H. Verschelde, and F. Verstraete, Matrix product states for gauge field theories, Phys. Rev. Lett. 113, 091601 (2014).
- M. C. Bañuls, K. Cichy, K. Jansen, and H. Saito, Chiral condensate in the Schwinger model with matrix product operators, Phys. Rev. D 93, 094512 (2016).
- B. Buyens, J. Haegeman, H. Verschelde, F. Verstraete, and K. Van Acoleyen, Confinement and string breaking for in the Hamiltonian picture, Phys. Rev. X 6, 041040 (2016).
- B. Buyens, F. Verstraete, and K. Van Acoleyen, Hamiltonian simulation of the Schwinger model at finite temperature, Phys. Rev. D 94, 085018 (2016).
- Y. Shimizu and Y. Kuramashi, Berezinskii-Kosterlitz-Thouless transition in lattice Schwinger model with one flavor of Wilson fermion, Phys. Rev. D 97, 034502 (2018).
- L. Funcke, K. Jansen, and S. Kühn, Topological vacuum structure of the Schwinger model with matrix product states, Phys. Rev. D 101, 054507 (2020).
- M. Honda, E. Itou, Y. Kikuchi, L. Nagano, and T. Okuda, Classically emulated digital quantum simulation for screening and confinement in the Schwinger model with a topological term, Phys. Rev. D 105, 014504 (2022).
- E. Itou, A. Matsumoto, and Y. Tanizaki, DMRG study of the theta-dependent mass spectrum in the 2-flavor Schwinger model, J. High Energy Phys. 09 (2024) 155.
- M. Fishman, S. R. White, and E. M. Stoudenmire, The ITensor Software Library for Tensor Network Calculations, SciPost Phys. Codebases 4 (2022).10.21468/SciPostPhysCodeb.4
- M. Fishman, S. R. White, and E. M. Stoudenmire, Codebase release 0.3 for ITensor, SciPost Phys. Codebases 4-r0.3 (2022).10.21468/SciPostPhysCodeb.4-r0.3
- J. B. Kogut and L. Susskind, Hamiltonian formulation of Wilson’s lattice gauge theories, Phys. Rev. D 11, 395 (1975).
- T. Banks, L. Susskind, and J. Kogut, Strong-coupling calculations of lattice gauge theories: ()-dimensional exercises, Phys. Rev. D 13, 1043 (1976).
- C. J. Hamer, W.-h. Zheng, and J. Oitmaa, Series expansions for the massive Schwinger model in Hamiltonian lattice theory, Phys. Rev. D 56, 55 (1997).
- Z. Komargodski, K. Ohmori, K. Roumpedakis, and S. Seifnashri, Symmetries and strings of adjoint , J. High Energy Phys. 03 (2021) 103.
- A. Cherman, T. Jacobson, M. Shifman, M. Unsal, and A. Vainshtein, Four-fermion deformations of the massless Schwinger model and confinement, J. High Energy Phys. 01 (2023) 087.
- A. Bondi, G. Curci, G. Paffuti, and P. Rossi, Metric and central charge in the perturbative approach to two-dimensional fermionic models, Ann. Phys. (N.Y.) 199, 268 (1990).
- L. Susskind, Lattice fermions, Phys. Rev. D 16, 3031 (1977).
- M. C. Banuls, K. Cichy, Y.-J. Kao, C. J. D. Lin, Y.-P. Lin, and D. T. L. Tan, Investigation of the dimensional Thirring model using the method of matrix product states, Proc. Sci., LATTICE2018 (2018) 229.
- C. Hamer, J. Kogut, D. Crewther, and M. Mazzolini, The massive Schwinger model on a lattice: Background field, chiral symmetry and the string tension, Nucl. Phys. B208, 413 (1982).
- C. Nagele, J. E. Cejudo, T. Byrnes, and M. Kleban, Flux unwinding in the lattice Schwinger model, Phys. Rev. D 99, 094501 (2019).
- E. Fradkin and L. Susskind, Order and disorder in gauge systems and magnets, Phys. Rev. D 17, 2637 (1978).
- M. E. Fisher and M. N. Barber, Scaling theory for finite-size effects in the critical region, Phys. Rev. Lett. 28, 1516 (1972).
- C. J. Hamer and M. N. Barber, Finite lattice methods in quantum Hamiltonian field theory. 1. The Ising model, J. Phys. A 14, 241 (1981).
- J. L. Cardy, Conformal invariance and universality in finite-size scaling, J. Phys. A 17, L385 (1984).
- A. A. Belavin, A. M. Polyakov, and A. B. Zamolodchikov, Infinite conformal symmetry in two-dimensional quantum field theory, Nucl. Phys. B241, 333 (1984).
- J. L. Cardy, Effect of boundary conditions on the operator content of two-dimensional conformally invariant theories, Nucl. Phys. B275, 200 (1986).
- P. Calabrese and J. L. Cardy, Entanglement entropy and quantum field theory, J. Stat. Mech. (2004) P06002.
- P. Calabrese and J. Cardy, Entanglement entropy and conformal field theory, J. Phys. A 42, 504005 (2009).
- I. Affleck and A. W. W. Ludwig, Universal noninteger ground-state degeneracy in critical quantum systems, Phys. Rev. Lett. 67, 161 (1991).
- M. Campostrini, A. Pelissetto, and E. Vicari, Finite-size scaling at quantum transitions, Phys. Rev. B 89, 094516 (2014).
- T. Okuda, Schwinger model on an interval: Analytic results and DMRG, Phys. Rev. D 107, 054506 (2023).
- M. Honda, E. Itou, and Y. Tanizaki, DMRG study of the higher-charge Schwinger model and its ’t Hooft anomaly, J. High Energy Phys. 11 (2022) 141.
- B.-X. Lao and S. Rychkov, 3D Ising CFT and exact diagonalization on icosahedron: The power of conformal perturbation theory, SciPost Phys. 15, 243 (2023).
- I. P. McCulloch, From density-matrix renormalization group to matrix product states, J. Stat. Mech. (2007) P10014.
- G. M. Crosswhite and D. Bacon, Finite automata for caching in matrix product algorithms, Phys. Rev. A 78, 012356 (2008).
- G. M. Crosswhite, A. C. Doherty, and G. Vidal, Applying matrix product operators to model systems with long-range interactions, Phys. Rev. B 78, 035116 (2008).
- U. Schollwöck, The density-matrix renormalization group in the age of matrix product states, Ann. Phys. (Amsterdam) 326, 96 (2011), January 2011 Special Issue.
- S. R. White, Spin gaps in a frustrated Heisenberg model for , Phys. Rev. Lett. 77, 3633 (1996).