{"paper_id":"2ebebc87-b42d-465e-bc83-cb4b32c1250f","body_text":"Raman fingerprint of high-temperature superconductivity in compressed hydrides | 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 Physical Sciences - Article Raman fingerprint of high-temperature superconductivity in compressed hydrides Federico Aiace Gorelli, Philip Dalladay-Simpson, Guglielmo Marchese, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8105210/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 discovery of high-temperature superconductivity in hydrogen-rich compounds under extreme pressures has prompted great excitement, intense research, but also debate over the past decade. Electrical transport has been the primary diagnostic tool for identifying superconductivity in these systems, whereas complementary probes, including magnetic, spectroscopic, tunnelling and ultrafast methods, remain mostly qualitative due to experimental constraints and sample heterogeneity. Recent concerns over their reliability have fuelled controversy, leading to scepticism and pointing out the need for alternative, quantitative approaches. In this study, we acquired unprecedented high-quality Raman spectra of hexagonal LaH10 at approximately 145 GPa and low temperatures, in conjunction with electrical transport measurements. Upon cooling, we observe a drop of resistivity and simultaneous remarkable variations of phonon frequencies and linewidths. These effects are interpreted and perfectly reproduced by the Migdal–Eliashberg theory, providing a definitive proof of phonon-mediated superconductivity and enabling a quantitative determination of the superconducting energy gap. Our results establish Raman spectroscopy as a robust, contact-free probe with micrometric resolution for studying high temperature superconductivity, opening a powerful route to its discovery and characterization. Physical sciences/Physics/Condensed-matter physics/Superconducting properties and materials Physical sciences/Physics/Techniques and instrumentation/Optical spectroscopy/Raman spectroscopy Raman high-pressure superconductivity electron-phonon Full Text Additional Declarations There is NO Competing Interest. Supplementary Files LaH10SItosubmit.pdf SUPPLEMENTARY INFORMATION 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-8105210\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":true,\"archivedVersions\":[],\"articleType\":\"Physical Sciences - Article\",\"associatedPublications\":[],\"authors\":[{\"id\":545691159,\"identity\":\"15564589-8d00-4e4d-94af-89b24164d038\",\"order_by\":0,\"name\":\"Federico Aiace Gorelli\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3klEQVRIie2QsQrCMBRFEwrJ8tD1DWJ+IaVQ3Bz9jbjURcFJOklBiJO7nyMEdCl+gYMuTg4ZHU2KHVzSjg45wyMh73AvISQS+VfuaxwPvmfgO0JOnYqSmLFWAeOUTkdJMtftBfx6SBGzw+Ou5GSh+cFYqm8j4IQaG1DS+pJJV2yl4Vog1U+ApKNYeiwYNgouc0K1gWkPhb+dsmDilVmvdKYILJj/McUQJPZSJJwTXyzVsMxRXb1Cq1MdStlram25FUNeZ9ZuzBSGxtgylPJTQTWTVgHBpYSfI5FIJOL4AGVxRLf/G+4+AAAAAElFTkSuQmCC\",\"orcid\":\"https://orcid.org/0000-0001-5634-6885\",\"institution\":\"Shanghai Advanced Research in Physical Sciences (SHARPS)\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Federico\",\"middleName\":\"Aiace\",\"lastName\":\"Gorelli\",\"suffix\":\"\"},{\"id\":545691160,\"identity\":\"38dd73ab-bf8f-454f-a4b1-98391b7011ea\",\"order_by\":1,\"name\":\"Philip Dalladay-Simpson\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0002-6213-4472\",\"institution\":\"Center for High Pressure Science and Technology Advanced Research\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Philip\",\"middleName\":\"\",\"lastName\":\"Dalladay-Simpson\",\"suffix\":\"\"},{\"id\":545691161,\"identity\":\"d2d7b180-24aa-4f3f-b521-61e45813379c\",\"order_by\":2,\"name\":\"Guglielmo Marchese\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0002-0732-1320\",\"institution\":\"Sapienza University of Rome\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Guglielmo\",\"middleName\":\"\",\"lastName\":\"Marchese\",\"suffix\":\"\"},{\"id\":545691162,\"identity\":\"87c756d1-bd16-43c1-9ebb-513786deb886\",\"order_by\":3,\"name\":\"Zi-yu Cao\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0002-4225-1583\",\"institution\":\"Liaocheng University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Zi-yu\",\"middleName\":\"\",\"lastName\":\"Cao\",\"suffix\":\"\"},{\"id\":545691163,\"identity\":\"41aed9d2-cd75-4880-855d-4bc38aea1625\",\"order_by\":4,\"name\":\"Paolo Barone\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0001-7222-8627\",\"institution\":\"SPIN-CNR Institute for Superconducting and other Innovative Materials and Devices\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Paolo\",\"middleName\":\"\",\"lastName\":\"Barone\",\"suffix\":\"\"},{\"id\":545691164,\"identity\":\"ddbda713-88bc-4a4e-862d-fb6ad89f0dbf\",\"order_by\":5,\"name\":\"Lara Benfatto\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0002-6091-3552\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Lara\",\"middleName\":\"\",\"lastName\":\"Benfatto\",\"suffix\":\"\"},{\"id\":545691165,\"identity\":\"5a34eb8b-673b-4d1a-9ba0-269bf88f429b\",\"order_by\":6,\"name\":\"Gaston Garbarino\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0003-4780-9520\",\"institution\":\"European Synchrotron Radiation Facility\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Gaston\",\"middleName\":\"\",\"lastName\":\"Garbarino\",\"suffix\":\"\"},{\"id\":545691166,\"identity\":\"c5d820bd-e479-4505-84c7-c5356bea10ca\",\"order_by\":7,\"name\":\"Francesco Mauri\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0002-6666-4710\",\"institution\":\"Dipartimento di Fisica, Università di Roma La Sapienza\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Francesco\",\"middleName\":\"\",\"lastName\":\"Mauri\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2025-11-13 11:31:03\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-8105210/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-8105210/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":98433948,\"identity\":\"61f30756-f709-4273-93ea-46a2f391a689\",\"added_by\":\"auto\",\"created_at\":\"2025-12-17 16:51:16\",\"extension\":\"pdf\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":9046791,\"visible\":true,\"origin\":\"\",\"legend\":\"Article File\",\"description\":\"\",\"filename\":\"LaH10maintosubmit.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8105210/v1_covered_02aa9812-a5b7-43ce-99c7-0045c08dad1b.pdf\"},{\"id\":96130354,\"identity\":\"f289051a-d0b9-4002-87e2-b1550d988202\",\"added_by\":\"auto\",\"created_at\":\"2025-11-18 02:09:29\",\"extension\":\"pdf\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"supplement\",\"size\":16460645,\"visible\":true,\"origin\":\"\",\"legend\":\"SUPPLEMENTARY INFORMATION\",\"description\":\"\",\"filename\":\"LaH10SItosubmit.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8105210/v1/4c569e6f32dbbe04fd62d62e.pdf\"}],\"financialInterests\":\"There is \\u003cb\\u003eNO\\u003c/b\\u003e Competing Interest.\",\"formattedTitle\":\"Raman fingerprint of high-temperature superconductivity in compressed hydrides\",\"fulltext\":[],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":false,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":true,\"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\":\"info@researchsquare.com\",\"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\":\"Raman, high-pressure, superconductivity, electron-phonon\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-8105210/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-8105210/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"The discovery of high-temperature superconductivity in hydrogen-rich compounds under extreme pressures has prompted great excitement, intense research, but also debate over the past decade. Electrical transport has been the primary diagnostic tool for identifying superconductivity in these systems, whereas complementary probes, including magnetic, spectroscopic, tunnelling and ultrafast methods, remain mostly qualitative due to experimental constraints and sample heterogeneity. Recent concerns over their reliability have fuelled controversy, leading to scepticism and pointing out the need for alternative, quantitative approaches. In this study, we acquired unprecedented high-quality Raman spectra of hexagonal LaH10 at approximately 145 GPa and low temperatures, in conjunction with electrical transport measurements. Upon cooling, we observe a drop of resistivity and simultaneous remarkable variations of phonon frequencies and linewidths. These effects are interpreted and perfectly reproduced by the Migdal–Eliashberg theory, providing a definitive proof of phonon-mediated superconductivity and enabling a quantitative determination of the superconducting energy gap. Our results establish Raman spectroscopy as a robust, contact-free probe with micrometric resolution for studying high temperature superconductivity, opening a powerful route to its discovery and characterization.\",\"manuscriptTitle\":\"Raman fingerprint of high-temperature superconductivity in compressed hydrides\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2025-11-18 02:09:25\",\"doi\":\"10.21203/rs.3.rs-8105210/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"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\":\"fb13d862-3108-4e09-b486-521047cab6ba\",\"owner\":[],\"postedDate\":\"November 18th, 2025\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"posted\",\"subjectAreas\":[{\"id\":58056387,\"name\":\"Physical sciences/Physics/Condensed-matter physics/Superconducting properties and materials\"},{\"id\":58056388,\"name\":\"Physical sciences/Physics/Techniques and instrumentation/Optical spectroscopy/Raman spectroscopy\"}],\"tags\":[],\"updatedAt\":\"2025-12-15T10:51:00+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2025-11-18 02:09:25\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-8105210\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-8105210\",\"identity\":\"rs-8105210\",\"version\":[\"v1\"]},\"buildId\":\"8U1c8b4HqxoKbykW_rLl7\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}