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arXiv · 2502.03556

Emulation of satellite up-link quantum communication with entangled photons

Thomas Jaeken·Alexander Pickston·Faris Redza·Thomas Jennewein·Alessandro Fedrizzi
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Abstract

Quantum communication rates in terrestrial quantum networks are fundamentally limited by fibre loss, even in the presence of quantum repeaters. Satellites offer a solution for long-distance communication, with the most commonly explored scenario involving prepare-and-measure protocols connecting from orbit to a trusted-node ground station via free-space down-links. In contrast, up-link scenarios allow for entanglement to be distributed between a satellite and remote end users in terrestrial networks, eliminating any trust requirement on the ground station. Here we demonstrate an ultra-bright source of far-non-degenerate entangled photons and perform quantum key distribution in emulated high-loss satellite scenarios. With a loss profile corresponding to that of one of the pioneering Micius up-link experiments, and a terrestrial end user separated by 10~km of telecom fibre we achieve secure key bit accumulation of 5.2~kbit in a single emulated overpass in the asymptotic limit. Our results confirm the viability of upcoming low-Earth orbit receiver satellite missions.

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Thomas Jaeken, Alexander Pickston, Faris Redza, Thomas Jennewein, Alessandro Fedrizzi. 2025-02-05. Emulation of satellite up-link quantum communication with entangled photons. https://doi.org/10.1364/opticaq.559266

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