Suppressing nonperturbative gauge errors in the thermodynamic limit using local pseudogenerators
Year: 2025
Authors: Van Damme M., Mildenberger J., Grusdt F., Hauke P., Halimeh J.C.
Autors Affiliation: Univ Ghent, Dept Phys & Astron, Krijgslaan 281, B-9000 Ghent, Belgium; Univ Trento, INO CNR BEC Ctr, Via Sommarive 14, I-38123 Trento, Italy; Univ Trento, Dept Phys, Via Sommarive 14, I-38123 Trento, Italy; Ludwig Maximilians Univ Munchen, Dept Phys, Theresienstr 37, D-80333 Munich, Germany; Ludwig Maximilians Univ Munchen, Arnold Sommerfeld Ctr Theoret Phys ASC, Theresienstr 37, D-80333 Munich, Germany; Munich Ctr Quantum Sci & Technol MCQST, Schellingstr 4, D-80799 Munich, Germany; Max Planck Inst Quantum Opt, D-85748 Garching, Germany; Ludwig Maximilian Univ Munich, Dept Phys, D-80333 Munich, Germany; Ludwig Maximilian Univ Munich, Arnold Sommerfeld Ctr Theoret Phys ASC, D-80333 Munich, Germany; Munich Ctr Quantum Sci & Technol MCQST, D-80799 Munich, Germany.
Abstract: With recent progress in quantum simulations of lattice-gauge theories, it is becoming a pressing question how to reliably protect the gauge symmetry that defines such models. Recently, an experimentally feasible gauge-protection scheme has been proposed that is based on the concept of a local pseudogenerator, which is required to act identically to the full gauge-symmetry generator in the target gauge sector, but not necessarily outside of it. The scheme has been analytically and numerically shown to reliably stabilize lattice gauge theories in the presence of perturbative errors on finite-size analog quantum-simulation devices. In this work, through uniform matrix product state calculations, we demonstrate the efficacy of this scheme for nonperturbative errors in analog quantum simulators up to all accessible evolution times in the thermodynamic limit, where it is a priori neither established nor expected that this scheme will succeed. Our results indicate the presence of an emergent gauge symmetry in an adjusted gauge theory even in the thermodynamic limit, which is beyond our analytic predictions. Additionally, we show through quantum circuit model calculations that gauge protection with local pseudogenerators also successfully suppresses gauge violations on finite quantum computers that discretize time through Trotterization. Our results firm up the robustness and feasibility of the local pseudogenerator as a viable tool for enforcing gauge invariance in modern quantum simulators and noisy intermediate-scale quantum devices.
Journal/Review: COMMUNICATIONS PHYSICS
Volume: 8 (1) Pages from: 106-1 to: 106-12
More Information: We are grateful to Monika Aidelsburger, Annabelle Bohrdt, Lukas Homeier, Haifeng Lang, and Christian Schweizer for collaboration on related projects. This work is part of and supported by Provincia Autonoma di Trento, the ERC Starting Grant StrEnQTh (project ID 804305), the Google Research Scholar Award ProGauge, and Q@TN-Quantum Science and Technology in Trento, Research Foundation Flanders (G0E1520N, G0E1820N), and ERC grants QUTE (647905) and ERQUAF (715861). This research was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy-EXC-2111-390814868 and via DFG Research Unit FOR 2414 under project number 277974659. J.C.H. acknowledges funding by the Max Planck Society and the European Research Council (ERC) under the European Union’s Horizon Europe research and innovation program (Grant Agreement No. 101165667)-ERC Starting Grant QuSiGauge.KeyWords: Real-time Dynamics; Quantum Simulation; InvarianceDOI: 10.1038/s42005-025-02035-y
