arXiv:2305.14487 · Physical Review A

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

Published Jan 24, 2024• 9 citations

Abstract

We demonstrate a method to reduce the number of single-photon detectors (SPDs) required in multiparty quantum key distribution (QKD) networks by a factor of 2 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 multiuser QKD networks.

DOI: 10.1103/physreva.109.012618

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