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arXiv · 0803.3237

Memory effects in quantum channel discrimination

Giulio Chiribella·Giacomo M. D'Ariano·Paolo Perinotti
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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. For optimal discrimination and estimation of sets of unitary channels memory-assisted protocols are not required.

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Giulio Chiribella, Giacomo M. D'Ariano, Paolo Perinotti. 2008-04-02. Memory effects in quantum channel discrimination. https://doi.org/10.1103/physrevlett.101.180501

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