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arXiv · 1404.5799

Correlation evolution and monogamy of two geometric quantum discords in multipartite systems

Yan-Kui Bai·Ting-Ting Zhang·Li-Tao Wang·Z. D. Wang
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Abstract

We explore two different geometric quantum discords defined respectively via the trace norm (GQD-1) and Hilbert-Schmidt norm (GQD-2) in multipartite systems. A rigorous hierarchy relation is revealed for the two GQDs in a class of symmetric two-qubit $X$-shape states. For multiqubit pure states, it is found that both GQDs are related to the entanglement concurrence, with the hierarchy relation being saturated. Furthermore, we look into a four-partite dynamical system consisting of two cavities interacting with independent reservoirs. It is found that the GQD-2 can exhibit various sudden change behaviours, while the GQD-1 only evolves asymptotically, with the two GQDs exhibiting different monogamous properties.

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Yan-Kui Bai, Ting-Ting Zhang, Li-Tao Wang, Z. D. Wang. 2014-10-02. Correlation evolution and monogamy of two geometric quantum discords in multipartite systems. https://doi.org/10.1140/epjd%2Fe2014-50387-8

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