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Slice optimisation for high-speed Gaussian coherent state continuous variable quantum key distribution

Amanda Weerasinghe, Muataz Alhussein, He Li, A. Wonfor, Richard V. Penty

Published Jan 1, 2023• 0 citations
Publisher

Abstract

We demonstrate, for the first time, slice reconciliation with optimised guard bands on Gaussian modulated continuous variable quantum key distribution. We produce a record 5Mb/s key rate after 25 km transmission distance with multilevel slicing.
DOI
10.1364/cleo_at.2023.jth2a.26

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Gaussian modulated coherent state continuous variable quantum key distribution protocol is proven to provide high security while being compatible with classical coherent communication equipment. Here, we demonstrate a high-speed Gaussian modulated coherent state continuous variable quantum key distribution with a symbol rate of 40 MHz. Our system is consisted of field deployable data acquisition and processing hardware. We have also developed a software tool chain for recording data and parameter monitoring in real time. The data is then post processed to distill secret keys. We have achieved a secret key rate of 2.3 Mbps after all the post processing stages, at a transmission distance of 25 km.
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