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arXiv · 1302.3186

Requirements for two-source entanglement concentration

Mihai Vidrighin·Tim J. Bartley·Gaia Donati·Xian-Min Jin·Marco Barbieri·W. Steven Kolthammer·Animesh Datta·Ian A. Walmsley
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Abstract

Entanglement enhancement is a key task for quantum technologies. This operation performed on states produced by parametric down-conversion sources has been the object of several recent experimental investigations. In particular, conditional preparation by photon-subtraction has been shown to improve the entanglement of these states. Here we analyse the role played by non-Gaussian and Gaussian measurements in more general entanglement concentration operations performed on a pair of two-mode squeezed vacua. We find stringent requirements for achieving an improved entanglement enhancement by measuring jointly these two resource states.

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Mihai Vidrighin, Tim J. Bartley, Gaia Donati, Xian-Min Jin, Marco Barbieri, W. Steven Kolthammer, Animesh Datta, Ian A. Walmsley. 2013-02-13. Requirements for two-source entanglement concentration. https://doi.org/10.2478/qmetro-2013-0002

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