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arXiv:0803.3237 · Physical Review Letters

Memory Effects in Quantum Channel Discrimination

Giulio Chiribella, Giacomo Mauro D’Ariano, Paolo Perinotti

Published Oct 27, 2008• 159 citations
arXivHTMLPDF

Abstract

We consider quantum-memory assisted protocols for discriminating quantum channels. We show that for optimal discrimination of memory channels, memory assisted protocols are needed. This leads to a new notion of distance for channels with memory, based on the general theory of quantum testers. For discrimination and estimation of sets of independent unitary channels, we prove optimality of parallel protocols among all possible architectures.

DOI
10.1103/physrevlett.101.180501

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