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

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

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PJ Edwards, W N Cheung, H van Pham, G Ganesharajah, P Lynam, L Barbopoulos. 2000-08-04. A Note on Quantum Key Channel Efficiency and Security using Correlated Photon Beam Transmitters. https://arxiv.org/abs/quant-ph/0008013

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