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arXiv · 2006.16366

Optimal measurement preserving qubit channels

Spiros Kechrimparis·Joonwoo Bae
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Abstract

We consider the problem of discriminating qubit states that are sent over a quantum channel and derive a necessary and sufficient condition for an optimal measurement to be preserved by the channel. We apply the result to the characterization of optimal measurement preserving (OMP) channels for a given qubit ensemble, e.g., a set of two states or a set of multiple qubit states with equal a priori probabilities. Conversely, we also characterize qubit ensembles for which a given channel is OMP, such as unitary and depolarization channels. Finally, we show how the sets of OMP channels for a given ensemble can be constructed.

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Spiros Kechrimparis, Joonwoo Bae. 2020-06-29. Optimal measurement preserving qubit channels. https://arxiv.org/abs/2006.16366

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