Zero-error classical capacity of qubit channels cannot be superactivated

Jeonghoon Park; Soojoon Lee

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arXiv · 1205.5851

Zero-error classical capacity of qubit channels cannot be superactivated

Jeonghoon Park·Soojoon Lee

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Abstract

It was shown [T.S. Cubitt et al., IEEE Trans. Inform. Theory 57, 8114 (2011)] that there exist quantum channels where a single use cannot transmit classical information perfectly yet two uses can. This phenomenon is called the superactivation of the zero-error classical capacity which does not occur in classical channels. In this paper, it is shown that qubit channels cannot generate the superactivation.

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Jeonghoon Park, Soojoon Lee. 2012-05-26. Zero-error classical capacity of qubit channels cannot be superactivated. https://arxiv.org/abs/1205.5851

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