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arXiv:1005.1045 · Physical Review A

Family of continuous-variable entanglement criteria using general entropy functions

A. Saboia, Fabricio Toscano, Stephen Patrick Walborn

Published Mar 14, 2011• 46 citations
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Abstract

We derive a family of entanglement criteria for continuous-variable systems based on the R\'enyi entropy of complementary distributions. We show that these entanglement witnesses can be more sensitive than those based on second-order moments, as well as previous tests involving the Shannon entropy [Phys. Rev. Lett. 103, 160505 (2009)]. We extend our results to include the case of discrete sampling. We provide several numerical results which show that our criteria can be used to identify entanglement in a number of experimentally relevant quantum states.

DOI
10.1103/physreva.83.032307

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