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Improved discrimination of unitaries by entangled probes

G. Mauro D'Ariano·Paoloplacido Lo Presti·Matteo G. A. Paris
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Abstract

We consider the problem of discriminating among a set of unitaries by means of measurements performed on the state undergoing the transformation. We show that use of entangled probes improves the discrimination in the two following cases: i) for a set of unitaries that are the UIR of a group and, ii) for any pair of transformations provided that multiple uses of the channel are allowed.

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G. Mauro D'Ariano, Paoloplacido Lo Presti, Matteo G. A. Paris. 2002-04-09. Improved discrimination of unitaries by entangled probes. https://doi.org/10.1088/1464-4266/4/4/304

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