Evidence for Electron-hole Crystals in a Mott Insulator

Evidence for Electron-hole Crystals in a Mott Insulator | 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 Evidence for Electron-hole Crystals in a Mott Insulator Jiong Lu, Konstantin Novoselov, Zhizhan Qiu, Yixuan Han, Keian Noori, and 13 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3252299/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 03 Jun, 2024 Read the published version in Nature Materials → Version 1 posted You are reading this latest preprint version Abstract Strongly correlated electrons enable the realization of a plethora of quantum states of matter, such as Wigner crystallization, fractional quantum Hall effect, and high-temperature superconductivity. When correlated electrons and holes are allowed to coexist, they become intertwined and fuel the pursuit of quantum excitonic states harbouring counterflow superfluidity 1,2 and topological orders with long-range quantum entanglement 3,4 . While such collective quantum states have been reported in sophisticated multi-layered heterostructures 1,2,4–8 , realizing and controlling such quantum states in a single natural strongly correlated material has remained challenging due to the fast particle recombination. Here, we report the creation of imbalanced electron-hole crystals in a doped multi-orbital honeycomb Mott insulator, α-RuCl 3 , through gate-tunable non-invasive van der Waals (vdW) doping from graphene. The absence of layer separation allows the immediate visualization of electron-hole crystals via scanning tunneling microscopy (STM). Real-space imaging reveals two completely different charge orderings at the lower Hubbard band (LHB) and the upper Hubbard band (UHB) energies, whose origin can be attributed to the correlation-driven honeycomb hole crystal composed of hole-rich Ru sites and rotational symmetry breaking paired electron crystal composed of electron-rich Ru-Ru bonds, respectively. Moreover, a gate-induced transition of electron-hole crystals can be directly visualized, further corroborating their nature as correlation-driven charge crystals 9 . The realization and atom-resolved visualization of imbalanced electron-hole crystals in a doped multi-orbital honeycomb Mott insulator, combined with a gate-tunable electron reservoir, opens new doors in the search for exotic correlated bosonic states within strongly correlated materials 5,8,10–12 . Physical sciences/Materials science/Condensed-matter physics/Structure of solids and liquids Physical sciences/Materials science/Condensed-matter physics/Electronic properties and materials Physical sciences/Materials science/Condensed-matter physics/Quantum fluids and solids Physical sciences/Materials science/Condensed-matter physics/Surfaces, interfaces and thin films Physical sciences/Physics/Condensed-matter physics/Quantum fluids and solids Full Text Additional Declarations There is NO Competing Interest. Supplementary Files supplementaryinformation.docx Cite Share Download PDF Status: Published Journal Publication published 03 Jun, 2024 Read the published version in Nature Materials → 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. 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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-3252299","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Letter","associatedPublications":[],"authors":[{"id":283671464,"identity":"6b95873e-3c52-4936-a4a1-da951cceb427","order_by":0,"name":"Jiong 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When correlated electrons and holes are allowed to coexist, they become intertwined and fuel the pursuit of quantum excitonic states harbouring counterflow superfluidity\u003csup\u003e1,2\u003c/sup\u003e and topological orders with long-range quantum entanglement\u003csup\u003e3,4\u003c/sup\u003e. While such collective quantum states have been reported in sophisticated multi-layered heterostructures\u003csup\u003e1,2,4\u0026ndash;8\u003c/sup\u003e, realizing and controlling such quantum states in a single natural strongly correlated material has remained challenging due to the fast particle recombination. Here, we report the creation of imbalanced electron-hole crystals in a doped multi-orbital honeycomb Mott insulator, α-RuCl\u003csub\u003e3\u003c/sub\u003e, through gate-tunable non-invasive van der Waals (vdW) doping from graphene. The absence of layer separation allows the immediate visualization of electron-hole crystals \u003cem\u003evia\u003c/em\u003e scanning tunneling microscopy (STM). Real-space imaging reveals two completely different charge orderings at the lower Hubbard band (LHB) and the upper Hubbard band (UHB) energies, whose origin can be attributed to the correlation-driven honeycomb hole crystal composed of hole-rich Ru sites and rotational symmetry breaking paired electron crystal composed of electron-rich Ru-Ru bonds, respectively. Moreover, a gate-induced transition of electron-hole crystals can be directly visualized, further corroborating their nature as correlation-driven charge crystals\u003csup\u003e9\u003c/sup\u003e. The realization and atom-resolved visualization of imbalanced electron-hole crystals in a doped multi-orbital honeycomb Mott insulator, combined with a gate-tunable electron reservoir, opens new doors in the search for exotic correlated bosonic states within strongly correlated materials\u003csup\u003e5,8,10\u0026ndash;12\u003c/sup\u003e.\u003c/p\u003e","manuscriptTitle":"Evidence for Electron-hole Crystals in a Mott Insulator","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-27 01:43:20","doi":"10.21203/rs.3.rs-3252299/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-materials","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"nmat","sideBox":"Learn more about [Nature Materials](http://www.nature.com/nmat/)","snPcode":"","submissionUrl":"","title":"Nature Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Research","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"92be8f07-a6a7-4ee1-96aa-da10e2b59257","owner":[],"postedDate":"March 27th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":29860716,"name":"Physical sciences/Materials science/Condensed-matter physics/Structure of solids and liquids"},{"id":29860717,"name":"Physical sciences/Materials science/Condensed-matter physics/Electronic properties and materials"},{"id":29860718,"name":"Physical sciences/Materials science/Condensed-matter physics/Quantum fluids and solids"},{"id":29860719,"name":"Physical sciences/Materials science/Condensed-matter physics/Surfaces, interfaces and thin films"},{"id":29860720,"name":"Physical sciences/Physics/Condensed-matter physics/Quantum fluids and solids"}],"tags":[],"updatedAt":"2024-06-04T15:30:54+00:00","versionOfRecord":{"articleIdentity":"rs-3252299","link":"https://doi.org/10.1038/s41563-024-01910-3","journal":{"identity":"nature-materials","isVorOnly":false,"title":"Nature Materials"},"publishedOn":"2024-06-03 04:00:00","publishedOnDateReadable":"June 3rd, 2024"},"versionCreatedAt":"2024-03-27 01:43:20","video":"","vorDoi":"10.1038/s41563-024-01910-3","vorDoiUrl":"https://doi.org/10.1038/s41563-024-01910-3","workflowStages":[]},"version":"v1","identity":"rs-3252299","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3252299","identity":"rs-3252299","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}