Concurrence of ferroelectricity and metallicity in perovskite ultrathin films

Concurrence of ferroelectricity and metallicity in perovskite ultrathin films | 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 Concurrence of ferroelectricity and metallicity in perovskite ultrathin films Tao Li, Hongxu Duan, Zhihao Gao, Yan Li, Feiyan Hou, Junying Zhang, and 18 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8747287/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Ferroelectricity and metallicity are generally considered mutually exclusive phenomena, as free electrons in metals prevent the occurrence of Coulomb interactions necessary for stabilizing long-range ferroelectric order. Here, we realized the coexistence of ferroelectricity and metallicity in epitaxial (001)-oriented NdNiO3 ultrathin films within an optimal thickness range of 10~16 unit-cell. These films exhibited Fermi liquid-like behavior at room temperature, confirming their metallic nature. Their ferroelectricity is supported by a spontaneous polarization of 27 μC cm-2 and a Curie temperature of approximately 150°C, as determined via electrical and optical measurements. On the basis of first-principles calculations and experimental evidence, the ferroelectricity of NdNiO3 ultrathin films was attributed to switchable charge ordering states formed by Ni3+δ and Ni3-δ ions with particularly low energy barriers, thereby facilitating the coexistence of ferroelectric and metallic behaviors. These findings establish NdNiO3 ultrathin films as promising platforms for metallic ferroelectrics, with potential applications in next-generation quantum electronic devices. Physical sciences/Materials science/Condensed-matter physics/Ferroelectrics and multiferroics Physical sciences/Physics/Condensed-matter physics/Surfaces, interfaces and thin films ferroelectric metal perovskite NdNiO3 Fermi liquid charge ordering nickelate Full Text Additional Declarations There is NO Competing Interest. Supplementary Files ExtendedDatafinal.docx Extended Data file Cite Share Download PDF Status: Under Review 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. 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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-8747287","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Physical Sciences - Article","associatedPublications":[],"authors":[{"id":586806865,"identity":"56d138f9-df07-496e-ad2b-5f05c7f6b909","order_by":0,"name":"Tao 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