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arXiv · 0909.0147

Entropic Entanglement Criteria for Continuous Variables

S. P. Walborn·B. G. Taketani·A. Salles·F. Toscano·R. L. de Matos Filho
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Abstract

We derive several entanglement criteria for bipartite continuous variable quantum systems based on the Shannon entropy. These criteria are more sensitive than those involving only second-order moments, and are equivalent to well-known variance product tests in the case of Gaussian states. Furthermore, they involve only a pair of quadrature measurements, and will thus should prove extremely useful the experimental identification of entanglement.

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S. P. Walborn, B. G. Taketani, A. Salles, F. Toscano, R. L. de Matos Filho. 2009-09-01. Entropic Entanglement Criteria for Continuous Variables. https://doi.org/10.1103/physrevlett.103.160505

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