A Co-Optimization Qubit Mapping Algorithm viaTwo-Stage Search and Bidirectional Look

A Co-Optimization Qubit Mapping Algorithm viaTwo-Stage Search and Bidirectional Look | 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 Research Article A Co-Optimization Qubit Mapping Algorithm viaTwo-Stage Search and Bidirectional Look Kang Xu, Peian Chen, Yukun Wang, Dandan Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8363879/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Current quantum devices typically lack full qubit connectivity, making it difficult to directly execute logical circuits on quantum devices. This limitation necessitates quantum circuit mapping algorithms to insert SWAP gates, dynamically remapping logical qubits to physical qubits, and transforming logical circuits into physical circuits that comply with device connectivity constraints. However, the insertion of SWAP gates increases both the gate count and circuit depth, ultimately reducing the fidelity of quantum algorithms. To achieve a balanced optimization of these two objectives, we propose the TANGO algorithm. The algorithm first formulates an evaluation function that balances the impact of qubit mapping on both mapped and unmapped nodes is introduced to enhance initial mapping quality, thereby reducing the number of SWAP gates inserted during routing. Next, we design an innovative two-stage routing algorithm that prioritizes the number of executable gates as the primary evaluation metric while also considering quantum gate distance, circuit depth, {and a novel bidirectional-look SWAP strategy}, which optimizes SWAP gate selection in conjunction with preceding gates, improving the effectiveness of the mapping algorithm. Finally, by integrating advanced quantum gate optimization techniques, the algorithm's overall performance is further enhanced. Experimental results demonstrate that, compared to state-of-the-art methods, the proposed algorithm achieves multi-objective co-optimization of gate count and circuit depth across various benchmarks and quantum devices, exhibiting significant performance advantages. quantum computing qubit mapping collaborative optimization Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 24 Apr, 2026 Reviews received at journal 20 Apr, 2026 Reviewers agreed at journal 11 Apr, 2026 Reviewers agreed at journal 04 Apr, 2026 Reviewers agreed at journal 19 Jan, 2026 Reviewers invited by journal 07 Jan, 2026 Editor assigned by journal 23 Dec, 2025 Submission checks completed at journal 23 Dec, 2025 First submitted to journal 15 Dec, 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. We do this by developing innovative software and high quality services for the global research community. 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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-8363879","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":571413931,"identity":"59d41a8a-ea1c-47fc-8d2d-23781d2f6199","order_by":0,"name":"Kang Xu","email":"","orcid":"","institution":"China University of Petroleum, Beijing","correspondingAuthor":false,"prefix":"","firstName":"Kang","middleName":"","lastName":"Xu","suffix":""},{"id":571413933,"identity":"f398f01f-113a-40e2-ae40-1e61e411d7e5","order_by":1,"name":"Peian Chen","email":"","orcid":"","institution":"China University of Petroleum, Beijing","correspondingAuthor":false,"prefix":"","firstName":"Peian","middleName":"","lastName":"Chen","suffix":""},{"id":571413934,"identity":"ab5251fa-be2a-42b0-b075-b10fe53d102e","order_by":2,"name":"Yukun Wang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwklEQVRIiWNgGAWjYFACNiA2sJEDMQ88IF5LRZoxWEsC8VrOHEpsALGJ0mJwIy1NurDtQPr8sMMPgbbYyek2ENZyTHpm253cjbfTDIBako3NDhDQYnYjvU2at+1Z7sbZCSAtBxK3EanlcLrh7PQPxGoBOoznzOEEeekcIm2xP/Ms2ZqnIs1wg3ROwYEEAyL8ItmeZnibx8BGXn52+uYPHyrs5AhqYRBIgNAGYJUGhJSDAD/UUPkGYlSPglEwCkbBiAQACZZI/N0GW0IAAAAASUVORK5CYII=","orcid":"","institution":"China University of Petroleum, Beijing","correspondingAuthor":true,"prefix":"","firstName":"Yukun","middleName":"","lastName":"Wang","suffix":""},{"id":571413935,"identity":"23dfb879-d20f-411a-8275-6b7c7ad54e7a","order_by":3,"name":"Dandan Li","email":"","orcid":"","institution":"Beijing University of Posts and Telecommunications","correspondingAuthor":false,"prefix":"","firstName":"Dandan","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2025-12-15 08:53:48","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8363879/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8363879/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":99853771,"identity":"38ce4eb7-71fc-4413-9968-283249a797a2","added_by":"auto","created_at":"2026-01-09 05:05:44","extension":"json","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":5827,"visible":true,"origin":"","legend":"","description":"","filename":"a9e5446d230e47b494e0226f906ab1fe.json","url":"https://assets-eu.researchsquare.com/files/rs-8363879/v1/b70a3f4f1bed3a07b8836f63.json"},{"id":100356810,"identity":"731a181d-c609-474f-be00-6fa4cb7fa43d","added_by":"auto","created_at":"2026-01-16 07:17:37","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":892443,"visible":true,"origin":"","legend":"","description":"","filename":"ACoOptimizationQubitMappingAlgorithmviaTwoStageSearchandBidirectionalLook.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8363879/v1_covered_98af471d-427d-4c6d-aaca-1e786f63fb77.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A Co-Optimization Qubit Mapping Algorithm viaTwo-Stage Search and Bidirectional Look","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"epj-quantum-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"epjq","sideBox":"Learn more about [EPJ Quantum Technology](http://epjquantumtechnology.springeropen.com)","snPcode":"40507","submissionUrl":"https://submission.nature.com/new-submission/40507/3","title":"EPJ Quantum Technology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"quantum computing, qubit mapping, collaborative optimization","lastPublishedDoi":"10.21203/rs.3.rs-8363879/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8363879/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Current quantum devices typically lack full qubit connectivity, making it difficult to directly execute logical circuits on quantum devices. 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