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arXiv · 1203.1197

Distributed super dense coding over noisy channels

Zahra Shadman·Hermann Kampermann·Chiara Macchiavello·Dagmar Bruss
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Abstract

We study multipartite super dense coding in the presence of a covariant noisy channel. We investigate the case of many senders and one receiver, considering both unitary and non-unitary encoding. We study the scenarios where the senders apply local encoding or global encoding. We show that, up to some pre-processing on the original state, the senders cannot do better encoding than local, unitary encoding. We then introduce general Pauli channels as a significant example of covariant maps. Considering Pauli channels, we provide examples for which the super dense coding capacity is explicitly determined.

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Zahra Shadman, Hermann Kampermann, Chiara Macchiavello, Dagmar Bruss. 2012-03-06. Distributed super dense coding over noisy channels. https://doi.org/10.1103/physreva.85.052306

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