Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Optical Communications and Networking

Entanglement distribution over a polarization-stabilized aerial fiber

Yicheng Shi, Jing Su, Anouar Rahmouni, Pranish Shrestha, Mheni Merzouki, Gabriel Bello Portmann, Anne Lazenby, Mael Flament, Mehdi Namazi, Abdella Battou, Oliver Slattery, Thomas Gerrits

Published May 26, 2026• 1 citation
Publisher

Abstract

Distributing quantum entanglement over telecommunication fiber is a fundamental task in metropolitan-scale quantum networks, enabling advanced applications such as quantum-secured communication, quantum sensing, and distributed quantum computing. Although polarization entanglement is relatively easy to generate and manipulate, its distribution across deployed fibers is challenging because of the time-varying polarization transformations imposed by the fiber, which must be actively stabilized. In this work, we experimentally demonstrate the distribution of polarization-entangled photons over a 62 km, partially aerial fiber between the National Institute of Standards and Technology and the University of Maryland. With polarization stabilization applied to the fiber, we achieved a photon pair rate of approximately 1500s −1 and observed a time-averaged CHSH inequality parameter of S =2.34±0.37. During a continuous 24 h experiment, time-multiplexed polarization compensation sessions only cost 7.2% of the total link operation time, leaving an entanglement distribution uptime of 92.8%. Our results demonstrate the feasibility of distributing polarization-entangled photons over challenging fiber conditions, which is an important step toward the practical deployment of quantum networks.

DOI
10.1364/jocn.592521

Related papers

Entanglement distribution over a polarization-stabilized aerial fiber link

Yicheng Shi, Thomas Gerrits, Oliver Slattery +6 more

we experimentally demonstrate the distribution of polarization-entangled photons over a 62-km, partially-aerial fiber between the National Institute of Standards and Technology and the University of Maryland. With active polarization compensation applied to the fiber link, we observed a channel fidelity above 98%. Over the stabilized fiber link, we distributed approximately 1200 pairs of polarization-entangled photons per second over a course of 24 hours, with an average CHSH S-parameter value of 2.39 and a link up-time of 92.8% for entanglement distribution.

Quantum Computing, Communication, and Simulation•Mar 5, 2026•1 citation

Entanglement Distribution over a Polarization-Stabilized Aerial Fiber

Yicheng Shi, Jing Su, Anouar Rahmouni +9 more

We experimentally demonstrate the distribution of polarization-entangled photons across a 62-km, partially-aerial fiber. With polarization stabilization applied to the fiber link, we achieve a photon pair rate of approximately 1500 per second and observe a CHSH inequality violation with S=2.34.

quant-pharXiv:2601.11753•Jan 20, 2026•1 citation

Entanglement Distribution over a Polarization-Stabilized Aerial Fiber

Yicheng Shi, Jing Su, Anouar Rahmouni +9 more

We experimentally demonstrate the distribution of polarization-entangled photons between two laboratories connected by a 62-km, partially-aerial fiber. Using time-multiplexed polarization stabilization, we maintain a pair rate of 1500 s − 1 over 24 hours and achieve an average CHSH value of S = 2 . 39 ± 0 . 22.

•Jan 1, 2026•0 citations

Automated distribution of high-rate, high-fidelity polarization entangled photons using deployed metropolitan fibers

Alexander N. Craddock, Anne Lazenby, Gabriel Bello Portmann +3 more

Distributing high-fidelity, high-rate entanglement over telecommunication infrastructure is one of the main paths towards large-scale quantum networks, enabling applications such as quantum encryption and network protection, blind quantum computing, distributed quantum computing, and distributed quantum sensing. However, the fragile nature of entangled photons operating in real-world fiber infrastructure has historically limited continuous operation of such networks. Here, we present a fully automated system capable of distributing polarization entangled photons over a 34 km deployed fiber in New York City. We achieve end-to-end pair rates of nearly $5\times10^5$ pairs/s and entanglement fidelity of approximately $99\%$. Separately, we achieve 15 days of continuous distribution, with a network up-time of $99.84\%$. Our work paves the way for practical deployment of 24/7 entanglement-based networks with rates and fidelity adequate for many current and future use-cases.

arXiv:2404.08626•Apr 12, 2024•1 citation

Automated Distribution of Polarization-Entangled Photons Using Deployed New York City Fibers

Alexander N. Craddock, Anne Lazenby, Gabriel Bello Portmann +3 more

The distribution of high-fidelity high-rate entanglement over telecommunication infrastructure is one of the main paths toward large-scale quantum networks, enabling applications such as quantum encryption and network protection, blind quantum computing, distributed quantum computing, and distributed quantum sensing. However, the fragile nature of entangled photons operating in real-world fiber infrastructure has historically limited continuous operation of such networks. Here, we present a fully automated system capable of distributing polarization-entangled photons over a 34-km deployed fiber in New York City, achieving high rates of nearly 5 × 10 5 pairs/s. Separately, we demonstrate a high fidelity of approximately 99 % for rates up to 2 × 10 4 pairs/s. Lastly, we achieve 15 days of continuous distribution, with a network up-time of 99.84 % . Our work paves the way for practical deployment of always-on entanglement-based networks with rates and fidelity adequate for many current and future use cases. Published by the American Physical Society 2024

PRX Quantum•Aug 9, 2024•49 citations

Continuous entanglement distribution over a transnational 248 km fiber link

Sebastian Philipp Neumann, Alexander Büchner, Lukas Bulla +2 more

Abstract Reliable long-distance distribution of entanglement is a key technique for many quantum applications, most notably quantum key distribution. Here, we present a continuously working, trusted-node free international link between Austria and Slovakia, directly distributing polarization-entangled photon pairs via 248 km of deployed telecommunication fiber. Despite 79 dB loss, we observe stable detected pair rates of 9 s −1 over 110 h. We mitigate multi-pair detections with strict temporal filtering, enabled by nonlocal compensation of chromatic dispersion and superconducting nanowire detectors. Fully automatized active polarization stabilization keeps the entangled state’s visibility at 86% for altogether 82 h. In a quantum cryptography context, this corresponds to an asymptotic secure key rate of 1.4 bits/s and 258 kbit of total key, considering finite-key effects. Our work paves the way for low-maintenance, ultra-stable quantum communication over long distances, independent of weather conditions and time of day, thus constituting an important step towards the quantum internet.

arXiv:2203.12417•Nature Communications•Oct 17, 2022•133 citations
Distributing quantum entanglement over telecommunication fiber is a fundamental task in metropolitan-scale quantum networks, enabling advanced applications such as quantum-secured communication, quantum sensing, and distributed quantum computing. Although polarization entanglement is relatively easy to generate and manipulate, its distribution across deployed fibers is challenging because of the time-varying polarization transformations imposed by the fiber, which must be actively stabilized. In this work, we experimentally demonstrate the distribution of polarization-entangled photons over a 62 km, partially aerial fiber between the National Institute of Standards and Technology and the University of Maryland. With polarization stabilization applied to the fiber, we achieved a photon pair rate of approximately 1500s −1 and observed a time-averaged CHSH inequality parameter of S =2.34±0.37. During a continuous 24 h experiment, time-multiplexed polarization compensation sessions only cost 7.2% of the total link operation time, leaving an entanglement distribution uptime of 92.8%. Our results demonstrate the feasibility of distributing polarization-entangled photons over challenging fiber conditions, which is an important step toward the practical deployment of quantum networks.
we experimentally demonstrate the distribution of polarization-entangled photons over a 62-km, partially-aerial fiber between the National Institute of Standards and Technology and the University of Maryland. With active polarization compensation applied to the fiber link, we observed a channel fidelity above 98%. Over the stabilized fiber link, we distributed approximately 1200 pairs of polarization-entangled photons per second over a course of 24 hours, with an average CHSH S-parameter value of 2.39 and a link up-time of 92.8% for entanglement distribution.
Distributing high-fidelity, high-rate entanglement over telecommunication infrastructure is one of the main paths towards large-scale quantum networks, enabling applications such as quantum encryption and network protection, blind quantum computing, distributed quantum computing, and distributed quantum sensing. However, the fragile nature of entangled photons operating in real-world fiber infrastructure has historically limited continuous operation of such networks. Here, we present a fully automated system capable of distributing polarization entangled photons over a 34 km deployed fiber in New York City. We achieve end-to-end pair rates of nearly 5×1055\times10^55×105 pairs/s and entanglement fidelity of approximately 99%99\%99%. Separately, we achieve 15 days of continuous distribution, with a network up-time of 99.84%99.84\%99.84%. Our work paves the way for practical deployment of 24/7 entanglement-based networks with rates and fidelity adequate for many current and future use-cases.
The distribution of high-fidelity high-rate entanglement over telecommunication infrastructure is one of the main paths toward large-scale quantum networks, enabling applications such as quantum encryption and network protection, blind quantum computing, distributed quantum computing, and distributed quantum sensing. However, the fragile nature of entangled photons operating in real-world fiber infrastructure has historically limited continuous operation of such networks. Here, we present a fully automated system capable of distributing polarization-entangled photons over a 34-km deployed fiber in New York City, achieving high rates of nearly 5 × 10 5 pairs/s. Separately, we demonstrate a high fidelity of approximately 99 % for rates up to 2 × 10 4 pairs/s. Lastly, we achieve 15 days of continuous distribution, with a network up-time of 99.84 % . Our work paves the way for practical deployment of always-on entanglement-based networks with rates and fidelity adequate for many current and future use cases. Published by the American Physical Society 2024
Abstract Reliable long-distance distribution of entanglement is a key technique for many quantum applications, most notably quantum key distribution. Here, we present a continuously working, trusted-node free international link between Austria and Slovakia, directly distributing polarization-entangled photon pairs via 248 km of deployed telecommunication fiber. Despite 79 dB loss, we observe stable detected pair rates of 9 s −1 over 110 h. We mitigate multi-pair detections with strict temporal filtering, enabled by nonlocal compensation of chromatic dispersion and superconducting nanowire detectors. Fully automatized active polarization stabilization keeps the entangled state’s visibility at 86% for altogether 82 h. In a quantum cryptography context, this corresponds to an asymptotic secure key rate of 1.4 bits/s and 258 kbit of total key, considering finite-key effects. Our work paves the way for low-maintenance, ultra-stable quantum communication over long distances, independent of weather conditions and time of day, thus constituting an important step towards the quantum internet.