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Quantum data processing and error correction

Benjamin Schumacher·M. A. Nielsen
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Abstract

This paper investigates properties of noisy quantum information channels. We define a new quantity called {\em coherent information} which measures the amount of quantum information conveyed in the noisy channel. This quantity can never be increased by quantum information processing, and it yields a simple necessary and sufficient condition for the existence of perfect quantum error correction.

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Benjamin Schumacher, M. A. Nielsen. 1996-04-22. Quantum data processing and error correction. https://doi.org/10.1103/physreva.54.2629

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