Suspended thin-film lithium niobate modulator for broadband mid-infrared light modulation and frequency comb generation

Suspended thin-film lithium niobate modulator for broadband mid-infrared light modulation and frequency comb generation | 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 Suspended thin-film lithium niobate modulator for broadband mid-infrared light modulation and frequency comb generation Mengjie Yu, Chun-Ho Lee, Xinyi Ren, Xinzhou Su, Wonho Lee, Zile Jiang, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8310422/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 The mid-infrared (MIR) spectral region is central to sensing, spectroscopy, and free-space optical communication, yet coherent and broadband electro-optic (EO) control remains limited by material loss, bandwidth constraints, and high switching voltages. Existing approaches based on quantum cascade laser modulation, nonlinear frequency conversion, or bulk EO devices suffer from fundamental trade-offs between efficiency, bandwidth, and scalability. Here we report a suspended thin-film lithium niobate (TFLN) MIR EO platform co-designed with velocity- and impedance-matched traveling-wave microwave electrodes. We achieve record-low half-wave voltages of 2.3–4.3 V across 2.4–3.6 μm and EO bandwidths up to 50 GHz, corresponding to a record voltage-bandwidth figure-of-merit of 17.4 GHz/V. High-frequency operation with 4.5–6.5 V is demonstrated at 25–35 GHz, together with 30-GHz-line-spacing MIR EO frequency comb generation spanning 0.8 THz. We further validate the platform in a free-space communication link, establishing a scalable high-performance MIR optoelectronic platform. Physical sciences/Optics and photonics/Optical physics/Nanophotonics and plasmonics Physical sciences/Nanoscience and technology/Nanoscale devices/Nanophotonics and plasmonics Physical sciences/Optics and photonics/Optical physics/Nonlinear optics Full Text Additional Declarations Yes there is potential Competing Interest. C. L., Z.C. and M.Y. are involved in developing lithium niobate technologies at Opticore Inc.. 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-8310422","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":561308418,"identity":"23bd44a4-d822-4904-a2ff-620bde05cc1b","order_by":0,"name":"Mengjie 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