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Multiplicativity of Accessible Fidelity and Quantumness for Sets of Quantum States

K. M. R. Audenaert·C. A. Fuchs·C. King·A. Winter
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Abstract

Two measures of sensitivity to eavesdropping for alphabets of quantum states were recently introduced by Fuchs and Sasaki in quant-ph/0302092. These are the accessible fidelity and quantumness. In this paper we prove an important property of both measures: They are multiplicative under tensor products. The proof in the case of accessible fidelity shows a connection between the measure and characteristics of entanglement-breaking quantum channels.

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K. M. R. Audenaert, C. A. Fuchs, C. King, A. Winter. 2003-08-22. Multiplicativity of Accessible Fidelity and Quantumness for Sets of Quantum States. https://arxiv.org/abs/quant-ph/0308120

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