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arXiv · 1308.4810

Complete condition for nonzero quantum correlation in continuous variable systems

Chengjie Zhang·Sixia Yu·Qing Chen·Haidong Yuan·C. H. Lai·C. H. Oh
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Abstract

Quantum correlation provides a promising measure beyond entanglement. Here, we propose a necessary and sufficient condition for nonzero quantum correlation in continuous variable systems, which is simple and easy to perform in terms of a marker $Q_r$. In order to get this condition, we introduce continuous-variable local orthogonal bases of the operator space, which are generalized from the orthogonal basis sets in local operator space for discrete variables. Based on this, we obtain the marker $Q_r$ for all bipartite continuous variable states, and provide several examples including two-mode Gaussian and non-Gaussian states. Our result may provide a candidate for quantum correlation measures, and can be measured by designed quantum circuits.

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Chengjie Zhang, Sixia Yu, Qing Chen, Haidong Yuan, C. H. Lai, C. H. Oh. 2013-08-22. Complete condition for nonzero quantum correlation in continuous variable systems. https://doi.org/10.1088/1367-2630%2F17%2F9%2F093007

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