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arXiv · 2405.11990

Coherent Quantum Communications Across National Scale Telecommunication Infrastructure

Mirko Pittaluga·Yuen San Lo·Adam Brzosko·Robert I. Woodward·Matthew S. Winnel·Thomas Roger·James F. Dynes·Kim A. Owen·Sergio Juarez·Piotr Rydlichowski·Domenico Vicinanza·Guy Roberts·Andrew J. Shields
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Abstract

Quantum communications harness quantum phenomena like superposition and entanglement to enhance information transfer between remote nodes. Coherent quantum communications, essential for phase-based quantum internet architecture, require optical coherence among nodes and typically involve single-photon interference. Challenges like preserving optical coherence and integrating advanced single-photon detectors have impeded their deployment in existing telecommunication networks. This study introduces innovative approaches to the architecture and techniques supporting coherent quantum communications, marking their first successful integration within a commercial telecom infrastructure between Frankfurt and Kehl, Germany. Employing the Twin Field Quantum Key Distribution protocol, we achieved encryption key distribution at 110 bit/s over 254 km. This system features measurement-device-independent properties and non-cryogenically cooled detectors, and represents the first effective quantum repeater implementation on telecom infrastructure, the longest practical quantum key distribution deployment to date, and validates the feasibility of a phase-based quantum internet architecture.

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Mirko Pittaluga, Yuen San Lo, Adam Brzosko, Robert I. Woodward, Matthew S. Winnel, Thomas Roger, James F. Dynes, Kim A. Owen, Sergio Juarez, Piotr Rydlichowski, Domenico Vicinanza, Guy Roberts, Andrew J. Shields. 2024-05-20. Coherent Quantum Communications Across National Scale Telecommunication Infrastructure. https://arxiv.org/abs/2405.11990

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