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arXiv · 0910.4567

Detecting entanglement with non-hermitian operators

Mark Hillery·Ho Trung Dung·Julien Niset
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Abstract

We derive several entanglement conditions employing non-hermitian operators. We start with two conditions that were derived previously for field mode operators, and use them to derive conditions that can be used to show the existence of field-atom entanglement and entanglement between groups of atoms. The original conditions can be strengthened by making them invariant under certain sets of local unitary transformations, such as Gaussian operations. We then apply these conditions to several examples, such as the Dicke model. We conclude with a short discussion of how local uncertainty relations with non-hermitian operators can be used to derive entanglement conditions.

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Mark Hillery, Ho Trung Dung, Julien Niset. 2009-10-23. Detecting entanglement with non-hermitian operators. https://doi.org/10.1103/physreva.80.052335

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