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arXiv · 1301.7240

Upper bound and shareability of quantum discord based on entropic uncertainty relations

Ming-Liang Hu·Heng Fan
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Abstract

By using the quantum-memory-assisted entropic uncertainty relation (EUR), we derive a computable tight upper bound for quantum discord, which applies to an arbitrary bipartite state. Detailed examples show that this upper bound is tighter than other known bounds in a wide regime. Furthermore, we show that for any tripartite pure state, the quantum-memory-assisted EUR imposes a constraint on the shareability of quantum correlations among the constituent parties. This conclusion amends the well accepted result that quantum discord is not monogamous.

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Ming-Liang Hu, Heng Fan. 2013-07-30. Upper bound and shareability of quantum discord based on entropic uncertainty relations. https://doi.org/10.1103/physreva.88.014105

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