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arXiv:quant-ph/0008013

A Note on Quantum Key Channel Efficiency and Security using Correlated Photon Beam Transmitters

Edwards, PJ, W.N. Cheung, H van Pham, G. Ganesharajah, Lynam, P, L.O. Barbopoulos

Published Aug 3, 2000• 0 citations
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Abstract

Quantum-correlated photon sources provide a means of suppressing multiple photon emission and thus improving the security and efficiency of quasi single-photon quantum key distribution systems. We present illustrative photon-counting statistics for a Poissonian source conditioned by photon number measurements on a fully correlated twin beam with a non-ideal photon counter. We show that high photon counting efficiency is needed to obtain significant improvement in channel efficiency (bits per symbol) and/or security (in the form of reduced Shannon entropy leakage) over a single beam source.

DOI
10.48550/arxiv.quant-ph/0008013

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