IEEE Transactions on Information Theory

The capacity of the quantum channel with general signal states

Alexander Semenovich Holevo

Published Jan 1, 1998• 1,170 citations

Abstract

It is shown that the capacity of a classical-quantum channel with arbitrary (possibly mixed) states equals the maximum of the entropy bound with respect to all a priori distributions. This completes the recent result of Hausladen, Jozsa, Schumacher, Westmoreland, and Wootters (1996), who proved the equality for the pure state channel.

DOI: 10.1109/18.651037

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