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arXiv · 2603.11314

QuaNTUM: A Modular Quantum Communication Testbed for Scalable Fiber and Satellite Integration

Julien Chénedé·Tjorben Matthes·Josefine Krause·Asli Cakan·Tobias Vogl
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Abstract

Secure communication is essential for modern society, from financial transactions to critical infrastructure. As classical encryption faces threats from advancing computational power, quantum communication provides a fundamentally secure alternative based on physical laws. We present QuaNTUM (Quantum Network at the Technical University of Munich), a modular and extensible quantum communication testbed enabling scalable experiments across fiber-based campus networks and satellite-ground links. The terrestrial network connects research institutions in Garching near Munich via single-mode fibers in a star topology with polarization-maintaining components, multiplexers, and time-synchronized analysis modules. Active polarization control and real-time feedback support stable qubit transmission for high-fidelity quantum key distribution and entanglement distribution. A key feature is the integration of deterministic solid-state single-photon sources, including defects in hexagonal boron nitride and excited erbium atoms, with initial deployments on small satellites to bridge terrestrial and free-space channels. As an open-access platform, QuaNTUM enables protocol development, device benchmarking, and hybrid network research, providing a foundation for scalable quantum communication and future global quantum networks.

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Julien Chénedé, Tjorben Matthes, Josefine Krause, Asli Cakan, Tobias Vogl. 2026-03-11. QuaNTUM: A Modular Quantum Communication Testbed for Scalable Fiber and Satellite Integration. https://doi.org/10.1007/978-3-032-13852-1_12

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