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arXiv · 0809.1786

Geometric interpretation for A-fidelity and its relation with Bures fidelity

Zhihao Ma·Fu-Lin Zhang·Jing-Ling Chen
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Abstract

A geometric interpretation for the A-fidelity between two states of a qubit system is presented, which leads to an upper bound of the Bures fidelity. The metrics defined based on the A-fidelity are studied by numerical method. An alternative generalization of the A-fidelity, which has the same geometric picture, to a $N$-state quantum system is also discussed.

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Zhihao Ma, Fu-Lin Zhang, Jing-Ling Chen. 2008-12-30. Geometric interpretation for A-fidelity and its relation with Bures fidelity. https://doi.org/10.1103/physreva.78.064305

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