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Perfect Test of Entanglement for Two-level Systems

Sixia Yu·Jian-Wei Pan·Zeng-Bing Chen·Yong-De Zhang
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Abstract

A 3-setting Bell-type inequality enforced by the indeterminacy relation of complementary local observables is proposed as an experimental test of the 2-qubit entanglement. The proposed inequality has an advantage of being a sufficient and necessary criterion of the separability. Therefore any entangled 2-qubit state cannot escape the detection by this kind of tests. It turns out that the orientation of the local testing observables plays a crucial role in our perfect detection of the entanglement.

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Sixia Yu, Jian-Wei Pan, Zeng-Bing Chen, Yong-De Zhang. 2003-01-08. Perfect Test of Entanglement for Two-level Systems. https://doi.org/10.1103/physrevlett.91.217903

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