Hidden Spin-Splitting and Multiferroicity at the Surfaces of Antiferromagnets

Hidden Spin-Splitting and Multiferroicity at the Surfaces of Antiferromagnets | 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 Hidden Spin-Splitting and Multiferroicity at the Surfaces of Antiferromagnets Shifeng Qian, Qianmei Zhang, Yao Zhang, Xiaowei Sheng, Xiaodong Zhou, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8512912/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 Achieving controllable spin and ferroic functionalities in materials with collinear-compensated magnetic order is of paramount importance for the advancement of spintronics. Here, we reveal that natural surface symmetry breaking in common antiferromagnets (AFMs) provides a pervasive platform to simultaneously unlock hidden spin-splitting and emergent multiferroicity. Through a rigorous symmetry analysis, we classify the two-dimensional surfaces of three-dimensional AFMs into three distinct types. We show that while type-I surfaces retain spin degeneracy, type-II and type-III surfaces manifest spin-splitting, realizing altermagnetic and ferrimagnetic surface states, respectively. Importantly, the breaking of inversion symmetry at AFM surfaces generically allows spontaneous surface electric polarization for all three surface types, providing an excellent platform for magnetoelectric response. Furthermore, utilizing magnetic space groups, we establish specific symmetry criteria for identifying these surface types and screen material databases to propose representative candidates. Crucially, we show that this surface spin-splitting gives rise to emergent anomalous transport phenomena, such as an anomalous Hall effect explicitly confined to the surface, despite its absence in the bulk. Our findings reveal the rich magnetic structures and hidden spin splitting, multiferroicity, and magnetoelectric coupling at AFM surfaces, providing new fundamental insights and a viable route toward antiferromagnetic spintronic devices. Magnetism Magnetics Materials and Devices Full Text Additional Declarations The authors declare no competing interests. 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-8512912","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":569015299,"identity":"e1069b5e-cd86-413a-8739-99cd2315874c","order_by":0,"name":"Shifeng Qian","email":"","orcid":"","institution":"Anhui Province Key Laboratory for Control and Applications of Optoelectronic Information Materials, Department of Physics, Anhui Normal University, Anhui, Wuhu 241000, 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