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Additivity of the Classical Capacity of Entanglement-Breaking Quantum Channels

Peter W. Shor
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Abstract

We show that for the tensor product of an entanglement-breaking quantum channel with an arbitrary quantum channel, both the minimum entropy of an output of the channel and the Holevo-Schumacher-Westmoreland capacity are additive. In addition, for the tensor product of two arbitrary quantum channels, we give a bound involving entanglement of formation for the amount of subadditivity (for minimum entropy output) or superadditivity (for channel capacity) that can occur.

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Peter W. Shor. 2002-10-14. Additivity of the Classical Capacity of Entanglement-Breaking Quantum Channels. https://doi.org/10.1063/1.1498000

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