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arXiv · 2211.15108

Profitable entanglement for channel discrimination

Samad Khabbazi Oskouei·Stefano Mancini·Milajiguli Rexiti
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Abstract

We investigate the usefulness of side entanglement in discriminating between two generic qubit channels, {\ up to unitary pre- and post-processing,} and determine exact conditions under which it does enhance (as well as conditions under which it does not) the success probability. This is done in a constructive way by first analyzing the problem for channels that are extremal in the set of completely positive and trace-preserving qubit linear maps and then for channels that are inside such a set.

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Samad Khabbazi Oskouei, Stefano Mancini, Milajiguli Rexiti. 2022-11-28. Profitable entanglement for channel discrimination. https://doi.org/10.1098/rspa.2022.0796

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