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arXiv · 1504.04148

Correlation-based entanglement criterion in bipartite multiboson systems

Wieslaw Laskowski·Marcin Markiewicz·Danny Rosseau·Tim Byrnes·Kamil Kostrzewa·Adrian Kolodziejski
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Abstract

We describe a criterion for the detection of entanglement between two multi-boson systems. The criterion is based on calculating correlations of Gell-Mann matrices with a fixed boson number on each subsystem. This applies naturally to systems such as two entangled spinor Bose-Einstein condensates. We apply our criterion to several experimentally motivated examples, such as an $ S^z S^z $ entangled BECs, ac Stark shift induced two-mode squeezed BECs, and photons under parametric down conversion. We find that entanglement can be detected for all parameter regions for the most general criterion. Alternative criteria based on a similar formalism are also discussed together with their merits.

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Wieslaw Laskowski, Marcin Markiewicz, Danny Rosseau, Tim Byrnes, Kamil Kostrzewa, Adrian Kolodziejski. 2015-08-23. Correlation-based entanglement criterion in bipartite multiboson systems. https://doi.org/10.1103/physreva.92.022339

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