Quantum Information and Computation

The classical capacity achievable by a quantum channel assisted by a limited entanglement

Peter W. Shor

Published Dec 1, 2004• 26 citations

Abstract

Abstract: We give the trade-off curve showing the capacity of a quantum channel as a function of the amount of entanglement used by the sender and receiver for transmitting information. The endpoints of this curve are given by the Holevo-Schumacher-Westmoreland capacity formula and the entanglement-assisted capacity, which is the maximum over all input density matrices of the quantum mutual information. The proof we give is based on the Holevo-Schumacher-Westmoreland formula, and also gives a new and simpler proof for the entanglement-assisted capacity formula. 1

DOI: 10.5555/2011593.2011605

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