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arXiv · 1201.5092

Efficient entanglement criteria beyond Gaussian limits using Gaussian measurements

Hyunchul Nha·Su-Yong Lee·Se-Wan Ji·M. S. Kim
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Abstract

We present a formalism to derive entanglement criteria beyond the Gaussian regime that can be readily tested by only homodyne detection. The measured observable is the Einstein-Podolsky-Rosen (EPR) correlation. Its arbitrary functional form enables us to detect non-Gaussian entanglement even when an entanglement test based on second-order moments fails. We illustrate the power of our experimentally friendly criteria for a broad class of non-Gaussian states under realistic conditions. We also show rigorously that quantum teleportation for continuous variables employs a specific functional form of EPR correlation.

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Hyunchul Nha, Su-Yong Lee, Se-Wan Ji, M. S. Kim. 2012-01-24. Efficient entanglement criteria beyond Gaussian limits using Gaussian measurements. https://doi.org/10.1103/physrevlett.108.030503

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