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Fidelity and the communication of quantum information

Stephen M. Barnett·Claire R. Gilson·Masahide Sasaki
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Abstract

We compare and contrast the error probability and fidelity as measures of the quality of the receiver's measurement strategy for a quantum communications system. The error probability is a measure of the ability to retrieve {\it classical} information and the fidelity measures the retrieval of {\it quantum} information. We present the optimal measurement strategies for maximising the fidelity given a source that encodes information on the symmetric qubit-states.

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Stephen M. Barnett, Claire R. Gilson, Masahide Sasaki. 2001-07-05. Fidelity and the communication of quantum information. https://doi.org/10.1088/0305-4470%2F34%2F35%2F303

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