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arXiv · 1409.4600

Non-commutativity and Local Indistinguishability of Quantum States

Teng Ma·Ming-Jing Zhao·Yao-Kun Wang·Shao-Ming Fei
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Abstract

We study the local indistinguishability problem of quantum states. By introducing an easily calculated quantity, non-commutativity, we present an criterion which is both necessary and sufficient for the local indistinguishability of a complete set of pure orthogonal product states. A constructive distinguishing procedure to obtain the concrete local measurements and classical communications is given. The non-commutativity of ensembles can be also used to characterize the quantumness for classical-quantum or quantum-classical correlated states.

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Teng Ma, Ming-Jing Zhao, Yao-Kun Wang, Shao-Ming Fei. 2014-09-16. Non-commutativity and Local Indistinguishability of Quantum States. https://doi.org/10.1038/srep06336

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