Hybrid Quantum Repeaters with Ensemble-based Quantum Memories and Single-spin Photon Transducers

Hybrid Quantum Repeaters with Ensemble-based Quantum Memories and Single-spin Photon Transducers | 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 Hybrid Quantum Repeaters with Ensemble-based Quantum Memories and Single-spin Photon Transducers Johannes Borregaard, Johannes Borregaard, Fenglei Gu, Fenglei Gu, and 12 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4329745/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 20 Nov, 2025 Read the published version in npj Quantum Information → Version 1 posted 8 You are reading this latest preprint version Abstract Reliable quantum communication over hundreds of kilometers is a daunting yet necessary requirement for a quantum internet. To overcome photon loss, the deployment of quantum repeater stations between distant network nodes is necessary. A plethora of different quantum hardware is being developed for this purpose, each platform with its own opportunities and challenges. Here, we propose to combine two promising hardware platforms in a hybrid quantum repeater architecture to lower the cost and boost the performance of long-distance quantum communication. We outline how ensemble-based quantum memories combined with single-spin photon transducers, which can transfer quantum information between a photon and a single spin, can facilitate massive multiplexing, efficient photon generation, and quantum logic for amplifying communication rates. As a specific example, we describe how a single Rubidium (Rb) atom coupled to nanophotonic resonators can function as a high-rate, telecom-visible entangled photon source with the visible photon being compatible with storage in a Thulium-doped crystal memory (Tm-memory) and the telecom photon being compatible with low loss fiber propagation. We experimentally verify that Tm and Rb transitions are in resonance with each other. Our analysis shows that by employing up to 9 repeater stations, each equipped with two Tm-memories capable of holding up to 625 storage modes, along with four single Rb atoms, one can reach a quantum communication rate of about 10 secret bits per second across distances of up to 1000 km. Physical sciences/Physics/Quantum physics/Quantum information Physical sciences/Physics/Quantum physics/Single photons and quantum effects Physical sciences/Physics/Quantum physics/Quantum information Physical sciences/Physics/Quantum physics/Single photons and quantum effects Full Text Additional Declarations (Not answered) Cite Share Download PDF Status: Published Journal Publication published 20 Nov, 2025 Read the published version in npj Quantum Information → Version 1 posted Editorial decision: revise 18 Aug, 2024 Review # 1 received at journal 17 May, 2024 Reviewer # 2 agreed at journal 07 May, 2024 Reviewer # 1 agreed at journal 03 May, 2024 Reviewers invited by journal 30 Apr, 2024 Submission checks completed at journal 29 Apr, 2024 Editor assigned by journal 26 Apr, 2024 First submitted to journal 26 Apr, 2024 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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