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arXiv · 1211.0573

Collectibility for Mixed Quantum States

Łukasz Rudnicki·Zbigniew Puchała·Paweł Horodecki·Karol Życzkowski
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Abstract

Bounds analogous to entropic uncertainty relations allow one to design practical tests to detect quantum entanglement by a collective measurement performed on several copies of the state analyzed. This approach, initially worked out for pure states only [Phys. Rev. Lett. 107, 150502 (2011)], is extended here for mixed quantum states. We define collectibility for any mixed states of a multipartite system. Deriving bounds for collectibility for positive partially transposed states of given purity provides a new insight into the structure of entangled quantum states. In case of two qubits the application of complementary measurements and coincidence based detections leads to a new test of entanglement of pseudopure states.

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Łukasz Rudnicki, Zbigniew Puchała, Paweł Horodecki, Karol Życzkowski. 2012-11-02. Collectibility for Mixed Quantum States. https://doi.org/10.1103/physreva.86.062329

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