A conveyor-belt magneto-optical trap of CaF

A conveyor-belt magneto-optical trap of CaF | 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 A conveyor-belt magneto-optical trap of CaF Scarlett Yu, Jiaqi You, Yicheng Bao, Loïc Anderegg, Christian Hallas, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6340315/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 07 Jan, 2026 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Abstract Achieving high-density samples of laser-cooled molecules is a critical step toward advancing applications in precision measurements, ultracold chemistry and quantum science. We report the experimental realization of a high-density conveyor-belt magneto-optical trap for calcium monofluoride (CaF) molecules. The obtained highly-compressed cloud has a mean radius of 64(5) μ m and a peak number density of 3.6(5) x 10 10 cm -3 , a 600-fold increase over the conventional red-detuned MOTs of CaF, and the densest molecular MOT observed to date. Subsequent loading of these molecules into an optical dipole trap yields up to 2.6 x 10 4 trapped molecules at a temperature of 14(2) μ K with a peak phase-space density of ~2.4 x 10 -6 . This opens new possibilities for a range of applications utilizing high-density, optically trapped ultracold molecules. Physical sciences/Physics/Atomic and molecular physics/Ultracold gases Physical sciences/Physics/Atomic and molecular physics/Atomic and molecular interactions with photons Full Text Additional Declarations There is NO Competing Interest. Supplementary Files CaFconveyorMOTNatCommSuppMat.pdf A conveyor-belt magneto-optical trap of CaF Cite Share Download PDF Status: Published Journal Publication published 07 Jan, 2026 Read the published version in Nature Communications → 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6340315","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":437234619,"identity":"bdce593f-4939-456d-b4b5-2cf5108fdf1a","order_by":0,"name":"Scarlett 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