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

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 نشر من قبل Fulin Zhang
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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