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arXiv · 1301.6838

Reveal quantum correlation in complementary bases

Shengjun Wu·Zhihao Ma·Zhihua Chen·Sixia Yu
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Abstract

An essential feature of genuine quantum correlation is the simultaneous existence of correlation in complementary bases. We reveal this feature of quantum correlation by defining measures based on invariance under a basis change. For a bipartite quantum state, the classical correlation is the maximal correlation present in a certain optimum basis, while the quantum correlation is characterized as a series of residual correlations in the mutually unbiased bases. Compared with other approaches to quantify quantum correlation, our approach gives information-theoretical measures that directly reflect the essential feature of quantum correlation.

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Shengjun Wu, Zhihao Ma, Zhihua Chen, Sixia Yu. 2014-02-08. Reveal quantum correlation in complementary bases. https://doi.org/10.1038/srep04036

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