Electron tunneling into 2D semiconductors outside the tunnel junction

Electron tunneling into 2D semiconductors outside the tunnel junction | 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 Article Electron tunneling into 2D semiconductors outside the tunnel junction Lukas Novotny, Yang Xu, Nicolas Vetsch, Jian Zhang, Bhaskar Gharwi, and 12 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9278923/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 Electron tunneling is a central transport mechanism in nanoscale devices. The advent of two-dimensional (2D) van der Waals materials has greatly expanded the ability to explore unconventional tunneling phenomena in heterostructures. Conventionally, studies in these systems have focused on tunneling between a pair of electrodes separated by a barrier. Here we report a previously overlooked tunneling pathway in which electrons traverse both the barrier and the electrode to reach semiconductor layers placed outside the junction. We identify this mechanism through the observation of prominent conductance peaks in tunneling transport measurements. Combined transport and optical spectroscopy reveal that the conductance peaks are of different origin than the accompanying electroluminescence. While conductance peaks originate from electrons tunneling through the graphene-hBN-graphene barrier into empty states of the semiconductor, electroluminescence peaks originate from recombination of excitons excited via energy transfer. Our work uncovers the impact of the electronic environment adjacent to tunnel junctions and serves as a pristine probe of the material’s electronic properties. It also establishes a versatile platform for multidimensional investigations of tunneling processes, enabling new designs for on-chip optoelectronic applications. Physical sciences/Materials science/Nanoscale materials/Two-dimensional materials Physical sciences/Nanoscience and technology/Nanoscale devices/Electronic devices Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SITunnelinjectionyxfinalNMat.pdf Supplementary Info 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. 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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-9278923","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":617740795,"identity":"01c7389c-f2c0-4bd7-aefd-b42cb841a5da","order_by":0,"name":"Lukas 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