arXiv:1404.5033 · Physical Review Letters

Practical Receiver for Optimal Discrimination of Binary Coherent Signals

Сыч Денис Васильевич, Gerd Leuchs

Published Nov 8, 2016• 51 citations

Abstract

We address the long-standing problem of discriminating coherent states with the minimum error rate. We show an optimum receiver for coherent states which admits a relatively simple implementation with current technologies. The receiver is based on multichannel splitting of the signal, followed by feed-forward signal displacement and photon-counting detection. We develop an optimal control strategy for a finite signal split and show convergence of the error rate to the Helstrom bound.

DOI: 10.1103/physrevlett.117.200501

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