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arXiv · 2406.13916

A reconfigurable entanglement distribution network suitable for connecting multiple ground nodes with a satellite

Stéphane Vinet·Ramy Tannous·Thomas Jennewein
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Abstract

Satellite-based quantum communication channels are important for ultra-long distances. Given the short duration of a satellite pass, it can be challenging to efficiently connect multiple users of a city-wide network while the satellite is passing over that area. We propose a network with dual-functionality: during a brief satellite pass, the ground network is configured as a multipoint-to-point topology where all ground nodes establish entanglement with a satellite receiver. During times when this satellite is not available, the satellite up-link is rerouted via a single optical switch to the ground nodes, and the network is configured as a pair-wise ground network. We numerically simulate a pulsed hyper-entangled photon source and study the performance of the proposed network configurations for quantum key distribution. We find favourable scaling in the case that the satellite receiver exploits time-multiplexing whereas the ground nodes utilize frequency-multiplexing. The scalability, simple reconfigurability, and easy integration with fibre networks make this architecture a promising candidate for quantum communication of many ground nodes and a satellite, thus paving the way towards interconnection of ground nodes at a global scale.

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Stéphane Vinet, Ramy Tannous, Thomas Jennewein. 2024-06-20. A reconfigurable entanglement distribution network suitable for connecting multiple ground nodes with a satellite. https://doi.org/10.1140/epjqt%2Fs40507-025-00305-w

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