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arXiv · 2305.14487

Reducing the number of single-photon detectors in quantum key distribution networks by time multiplexing

Jakob Kaltwasser·Joschka Seip·Erik Fitzke·Maximilian Tippmann·Thomas Walther
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Abstract

We demonstrate a method to reduce the number of single-photon detectors (SPDs) required in multi-party quantum key distribution (QKD) networks by a factor of two by using detector time multiplexing (DTM). We implement the DTM scheme for an entanglement-based time-bin protocol and compare QKD results with and without DTM in our QKD network with four users. When small efficiency losses are acceptable, DTM enables cost-effective, scalable implementations of multi-user QKD networks.

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Jakob Kaltwasser, Joschka Seip, Erik Fitzke, Maximilian Tippmann, Thomas Walther. 2023-05-23. Reducing the number of single-photon detectors in quantum key distribution networks by time multiplexing. https://arxiv.org/abs/2305.14487

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