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arXiv · 0807.1781

An alternative quantum fidelity for mixed states of qudits

Xiaoguang Wang·Chang-Shui Yu·X. X. Yi
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Abstract

We give an alternative definition of quantum fidelity for two density operators on qudits in terms of the Hilbert-Schmidt inner product between them and their purity. It can be regarded as the well-defined operator fidelity for the two operators and satisfies all Jozsa's four axioms up to a normalization factor. One desire property is that it is not computationally demanding.

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Xiaoguang Wang, Chang-Shui Yu, X. X. Yi. 2008-07-11. An alternative quantum fidelity for mixed states of qudits. https://doi.org/10.1016/j.physleta.2008.10.083

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