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arXiv · 1604.07974

Non-convexity of private capacity and classical environment-assisted capacity of a quantum channel

David Elkouss·Sergii Strelchuk
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Abstract

The capacity of classical channels is convex. This is not the case for the quantum capacity of a channel: the capacity of a mixture of different quantum channels exceeds the mixture of the individual capacities and thus is non-convex. Here we show that this effect goes beyond the quantum capacity and holds for the private and classical environment-assisted capacities of quantum channels.

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David Elkouss, Sergii Strelchuk. 2016-04-27. Non-convexity of private capacity and classical environment-assisted capacity of a quantum channel. https://doi.org/10.1103/physreva.94.040301

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