QPSK Receiver outperforming the Standard Quantum Limit for any Signal Power

Christian R. Müller, Gerd Leuchs, Christoph Marquardt

Published Jan 1, 2014• 1 citation

Abstract

We present a quantum receiver for the discrimination of quadrature phase-shift keyed signals that approaches the Helstrom bound for any signal power. The discrimination is performed via adaptive displacements prior to a single photon detector.

DOI: 10.1364/cleo_qels.2014.fm3a.6

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