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arXiv · 2503.11564

High-fidelity entanglement between a telecom photon and a room-temperature quantum memory

Yang Wang·Alexander N. Craddock·Jaeda M. Mendoza·Rourke Sekelsky·Mael Flament·Mehdi Namazi
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Abstract

Entanglement distribution through existing telecommunication infrastructure is crucial for realizing large-scale quantum networks. However, distance limitations imposed by photon losses and the no-cloning theorem present significant challenges. Quantum repeaters based on entangled telecom wavelength photons and quantum memories offer a promising solution to overcome these limitations. In this work, we report an important milestone in quantum repeater architecture by demonstrating entanglement between a telecom-wavelength (1324 nm) photon and a room-temperature quantum memory with a fidelity up to 90.2%, using simple rubidium systems for both photon generation and storage. Furthermore, we achieve high-rate photon-memory entanglement generation of up to 1,200 Bell pairs per second with 80% fidelity. The technical simplicity and robustness of our room-temperature systems paves the way towards deploying quantum networks at scale in realistic settings.

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Yang Wang, Alexander N. Craddock, Jaeda M. Mendoza, Rourke Sekelsky, Mael Flament, Mehdi Namazi. 2025-03-14. High-fidelity entanglement between a telecom photon and a room-temperature quantum memory. https://arxiv.org/abs/2503.11564

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