Anomalous transport in U(1)-symmetric quantum circuits

Anomalous transport in U(1)-symmetric quantum circuits | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Anomalous transport in U(1)-symmetric quantum circuits Alessandro Summer, Alexander Nico-Katz, Shane Dooley, John Goold This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5925320/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 17 Jan, 2026 Read the published version in npj Quantum Information → Version 1 posted 11 You are reading this latest preprint version Abstract In this work we investigate discrete-time transport in a generic U(1)-symmetric disordered model tuned across an array of different dynamical regimes. We develop an aggregate quantity, a circular statistical moment, which is a simple function of the magnetization profile and which elegantly captures transport properties of the system. From this quantity we extract transport exponents, revealing behaviors across the phase diagram consistent with localized, diffusive, and - most interestingly for a disordered system - superdiffusive regimes. Investigation of this superdiffusive regime reveals the existence of a prethermal ''swappy'' regime unique to discrete-time systems in which excitations propagate coherently; even in the presence of strong disorder. Physical sciences/Physics/Information theory and computation Physical sciences/Physics/Quantum physics/Quantum information Physical sciences/Physics/Quantum physics/Quantum simulation Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 17 Jan, 2026 Read the published version in npj Quantum Information → Version 1 posted Editorial decision: Revision requested 13 Oct, 2025 Reviews received at journal 08 Sep, 2025 Reviews received at journal 01 Sep, 2025 Reviews received at journal 01 Sep, 2025 Reviewers agreed at journal 19 Jul, 2025 Reviewers agreed at journal 16 Jul, 2025 Reviewers agreed at journal 14 Jul, 2025 Reviewers invited by journal 09 Jul, 2025 Editor assigned by journal 31 Jan, 2025 Submission checks completed at journal 31 Jan, 2025 First submitted to journal 29 Jan, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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