Quantum non-signalling assisted zero-error classical capacity of qubit channels

Jeonghoon Park; Soojoon Lee

doi:10.1103/physreva.93.032334

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arXiv · 1510.05816

Quantum non-signalling assisted zero-error classical capacity of qubit channels

Jeonghoon Park·Soojoon Lee

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Abstract

In this paper, we explicitly evaluate the one-shot quantum non-signalling assisted zero-error classical capacities $\M_0^{\mathrm{QNS}}$ for qubit channels. In particular, we show that for nonunital qubit channels, $\M_0^{\mathrm{QNS}}=1$, which implies that in the one-shot setting, nonunital qubit channels cannot transmit any information with zero probability of error even when assisted by quantum non-signalling correlations. Furthermore, we show that for qubit channels, $\M_0^{\mathrm{QNS}}$ equals to the one-shot entanglement-assisted zero-error classical capacities. This means that for a single use of a qubit channel, quantum non-signalling correlations are not more powerful than shared entanglement.

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Jeonghoon Park, Soojoon Lee. 2015-10-20. Quantum non-signalling assisted zero-error classical capacity of qubit channels. https://doi.org/10.1103/physreva.93.032334

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