Long-range propagating paramagnon-polaritons in organic free radicals

Long-range propagating paramagnon-polaritons in organic free radicals | 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 Letter Long-range propagating paramagnon-polaritons in organic free radicals Sebastian Knauer, Roman Verba, Rostyslav O. Serha, Denys Slobodianiuk, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7990671/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 Materials are commonly distinguished by their magnetic response into diamagnetic, paramagnetic, and magnetically ordered (ferro-, ferri-, and antiferromagnetic) phases. Diamagnets and paramagnets lack spontaneous long-range order, whereas ordered magnets develop such order below their Curie or Néel temperature and support single spin-wave excitations (magnons). Magnons have found applications in radio-frequency technologies and computation 1– 4 , magneto-optics 5,6 , and foundational quantum experiments 7– 12 . Above the Curie/Néel temperature, longrange order is lost and the material transitions to a paramagnetic phase, with localised spin alignment in small patches, producing paramagnons with only short-range propagation. Here we show that long-range coherence is preserved in the organic free radical 2,2,6,6-tetramethylpiperidin-1-oxyl 13 above the Néel temperature using all-electrical propagating spin-wave spectroscopy in external magnetic fields. We observe coherently excited low-energy paramagnon-polaritons up to 23 GHz , propagating over 8 mm at supersonic group velocities exceeding 100 km s −1 . Using free radicals as magnon carriers integrates organic materials with spintronics and opens the way to organic electronics, dense information storage, and quantum technologies. Physical sciences/Physics/Condensed-matter physics/Magnetic properties and materials Physical sciences/Physics/Chemical physics Physical sciences/Physics/Condensed-matter physics/Molecular electronics Paramagnonics Propagating Spin-Wave Spectroscopy Millikelvin Temperature Magnonics Full Text Additional Declarations There is NO Competing Interest. Supplementary Files PropapagtingParamagnonPolaritonsNatMatLetterSI.pdf Supplementary Information for: Long-range propagating paramagnon-polaritons in organic free radicals 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. 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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-7990671","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Letter","associatedPublications":[],"authors":[{"id":543583153,"identity":"fb1a1e2e-5de2-4458-bf87-582db2dffe3a","order_by":0,"name":"Sebastian Knauer","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3UlEQVRIiWNgGAWjYBACCQSL+QCIlCFFC1sCiOQhRQuPAYgirEVydvMziY97GOz5pXs+v7pRY8HDwH746AZ8WqRljplJznjGkDhzztlt1jnHgA7jSUu7gU+LnESCmTTPAYYEgxu524xz2IBaJHjMCGhJ/yb95wCDvf2NnGfGOf+I0CItkWMmzXCAgXGDRA7z49w2IrRIzsgptuw5IJE4484xM+bcPgkeNkJ+kbiRvvHGjwM29vyzmx9/zvlWJ8fPfvgYXi0wnSCCDUISoRwOmD+QonoUjIJRMApGDgAAKHVB6/K83tIAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-5790-4575","institution":"University of Vienna","correspondingAuthor":true,"prefix":"","firstName":"Sebastian","middleName":"","lastName":"Knauer","suffix":""},{"id":543583154,"identity":"817353e1-87aa-4d00-9657-212acc319c5c","order_by":1,"name":"Roman Verba","email":"","orcid":"https://orcid.org/0000-0001-8811-6232","institution":"National Academy of Sciences of Ukraine","correspondingAuthor":false,"prefix":"","firstName":"Roman","middleName":"","lastName":"Verba","suffix":""},{"id":543583155,"identity":"c77cd6bf-40f4-4e05-b047-92d82cbfb417","order_by":2,"name":"Rostyslav O. 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Diamagnets and paramagnets lack spontaneous long-range order, whereas ordered magnets develop such order below their Curie or Néel temperature and support single spin-wave excitations (magnons). Magnons have found applications in radio-frequency technologies and computation\u003csup\u003e1– 4 \u003c/sup\u003e, magneto-optics\u003csup\u003e5,6\u003c/sup\u003e , and foundational quantum experiments\u003csup\u003e7– 12\u003c/sup\u003e . Above the Curie/Néel temperature, longrange order is lost and the material transitions to a paramagnetic phase, with localised spin alignment in small patches, producing paramagnons with only short-range propagation. Here we show that long-range coherence is preserved in the organic free radical 2,2,6,6-tetramethylpiperidin-1-oxyl\u003csup\u003e13\u003c/sup\u003e above the Néel temperature using all-electrical propagating spin-wave spectroscopy in external magnetic fields. We observe coherently excited low-energy paramagnon-polaritons up to 23 GHz , propagating over 8 mm at supersonic group velocities exceeding 100 km s\u003csup\u003e−1\u003c/sup\u003e . Using free radicals as magnon carriers integrates organic materials with spintronics and opens the way to organic electronics, dense information storage, and quantum technologies.\u003c/p\u003e","manuscriptTitle":"Long-range propagating paramagnon-polaritons in organic free radicals","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-13 06:07:57","doi":"10.21203/rs.3.rs-7990671/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","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}}],"origin":"","ownerIdentity":"e28b12f4-880f-4e02-8494-f235f13a7597","owner":[],"postedDate":"November 13th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":57830641,"name":"Physical sciences/Physics/Condensed-matter physics/Magnetic properties and materials"},{"id":57830642,"name":"Physical sciences/Physics/Chemical physics"},{"id":57830643,"name":"Physical sciences/Physics/Condensed-matter physics/Molecular electronics"}],"tags":[],"updatedAt":"2025-12-15T16:57:30+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-13 06:07:57","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7990671","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7990671","identity":"rs-7990671","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}