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Inseparability criterion for continuous variable systems

Lu-Ming Duan·G. Giedke·J. I. Cirac·P. Zoller
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Abstract

An inseparability criterion based on the total variance of a pair of Einstein-Podolsky-Rosen type operators is proposed for continuous variable systems. The criterion provides a sufficient condition for entanglement of any two-party continuous variable states. Furthermore, for all the Gaussian states, this criterion turns out to be a necessary and sufficient condition for inseparability.

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Lu-Ming Duan, G. Giedke, J. I. Cirac, P. Zoller. 2000-03-24. Inseparability criterion for continuous variable systems. https://doi.org/10.1103/physrevlett.84.2722

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