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Orthogonality And Distinguishability: Criterion For Local Distinguishability of Arbitrary Orthogonal States

Ping Xing Chen·Cheng Zu Li
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Abstract

We consider deeply the relation between the orthogonality and the distinguishability of a set of arbitrary states (including multi-partite states). It is shown that if a set of arbitrary states can be distinguished by local operations and classical communication (LOCC), \QTR{it}{\}each of the states can be written as a linear combination of product vectors such that all product vectors of one of the states are orthogonal to the other states. With this result we then prove a simple necessary condition for LOCC distinguishability of a class of orthogonal states. These conclusions may be useful in discussing the distinguishability of orthogonal quantum states further, understanding the essence of nonlocality and discussing the distillation of entanglement.

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Ping Xing Chen, Cheng Zu Li. 2003-11-14. Orthogonality And Distinguishability: Criterion For Local Distinguishability of Arbitrary Orthogonal States. https://doi.org/10.1103/physreva.68.062107

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