Hilbert subspace imprint: a new mechanism for non-thermalization

Hilbert subspace imprint: a new mechanism for non-thermalization | 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 Hilbert subspace imprint: a new mechanism for non-thermalization Shi-Xin Zhang, Hui Yu, Jiangping Hu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8609019/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The search for non-ergodic mechanisms in quantum many-body systems has become a frontier area of research in non-equilibrium physics.In this work, we introduce Hilbert subspace imprint (HSI)—a novel mechanism that enables evasion of thermalization and bridges the gap between quantum many-body scars (QMBS) and Hilbert space fragmentation (HSF). HSI manifests when initial states overlap exclusively with a polynomial scaling (with system size) set of eigenstates. We demonstrate this phenomenon through two distinct approaches: weak symmetry breaking and initial state engineering. In the former case, we observe that ferromagnetic states including those with a single spin-flip display non-thermal behavior under weak U(1) breaking, while antiferromagnetic states thermalize. In contrast, the Z2-symmetric model shows thermalization for both ferromagnetic and antiferromagnetic states. In the latter case, we engineer the initial state prepared by shallow quantum circuits that enhance the overlap with the small target subspace. Physical sciences/Physics/Quantum physics Physical sciences/Physics/Statistical physics, thermodynamics and nonlinear dynamics/Thermodynamics Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementalMaterial.pdf Supplemental Material for “Hilbert subspace imprint: a new mechanism for non-thermalization” Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8609019","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":581515778,"identity":"c47421b0-fcb8-4002-a7eb-d47535cf3129","order_by":0,"name":"Shi-Xin Zhang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+ElEQVRIie2RsWrDMBCGzxiSxeBVHUpfQZAHCH0T/wTixYRCIHQKCgFlClkDgfQV2s2jg6GT5qDBg7x46tLRW2xnyFTV2QrVx8FpuI/7DxE5HH8R5gmKqC3yTETZfYrPeyrX1iqD5t1DeTqsJSvT5Sw8bM6vZVpADHNDdfqzwovTmkMN5qxQCw1VQQRT7m2VRWFYGcgAQidTDZlDUEK+Jy3B9hAZJMNbo7x0SvhlV0h3WzjedfxJncJ+2cI1mltkhA+d+AwqH0lW8dPWGiyuHmq5xFHH5Xed5o+7cFKa2hbsRsCp+dbndjjrJRANTauMe047HA7HP+ICgaJeOTqluQ8AAAAASUVORK5CYII=","orcid":"","institution":"Institute of Physics, Chinese Academy of Sciences","correspondingAuthor":true,"prefix":"","firstName":"Shi-Xin","middleName":"","lastName":"Zhang","suffix":""},{"id":581515779,"identity":"b88e0e43-81ee-44e3-a8bc-d4e994b3ff45","order_by":1,"name":"Hui Yu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Hui","middleName":"","lastName":"Yu","suffix":""},{"id":581515780,"identity":"e43c9fd0-ff0f-487d-9648-234746c40ffc","order_by":2,"name":"Jiangping Hu","email":"","orcid":"https://orcid.org/0000-0002-4837-7742","institution":"Institute of Physics, Chinese Academy of Sciences","correspondingAuthor":false,"prefix":"","firstName":"Jiangping","middleName":"","lastName":"Hu","suffix":""}],"badges":[],"createdAt":"2026-01-15 09:30:44","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8609019/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8609019/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105729045,"identity":"89bcf2dc-cdfd-4eb2-99c7-dcf4ec1983fa","added_by":"auto","created_at":"2026-03-30 11:13:22","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3146677,"visible":true,"origin":"","legend":"Article File","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8609019/v1_covered_57d30eb9-1faa-4181-8346-a9d6977177ad.pdf"},{"id":101525548,"identity":"c6df4061-783b-4165-b59f-f0a4c3cef15a","added_by":"auto","created_at":"2026-01-30 18:16:36","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":2621886,"visible":true,"origin":"","legend":"Supplemental Material for \u0026#x201C;Hilbert subspace imprint: a new mechanism for non-thermalization\u0026#x201D;","description":"","filename":"SupplementalMaterial.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8609019/v1/9b95caf6d9e50e933b9304a6.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Hilbert subspace imprint: a new mechanism for non-thermalization","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8609019/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8609019/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"The search for non-ergodic mechanisms in quantum many-body systems has become a frontier area of research in non-equilibrium physics.In this work, we introduce Hilbert subspace imprint (HSI)—a novel mechanism that enables evasion of thermalization and bridges the gap between quantum many-body scars (QMBS) and Hilbert space fragmentation (HSF). 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