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arXiv:0909.0147 · Physical Review Letters

Entropic Entanglement Criteria for Continuous Variables

Stephen Patrick Walborn, Bruno G. Taketani, A. Salles, Fabricio Toscano, R. L. de Matos Filho

Published Oct 15, 2009• 100 citations
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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 prove extremely useful in the experimental identification of entanglement.

DOI
10.1103/physrevlett.103.160505

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