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Experimental Detection of Entanglement with Polarized Photons

M. Barbieri·F. De Martini·G. Di Nepi·P. Mataloni·G. M. D'Ariano·C. Macchiavello
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Abstract

We report on the first experimental realization of the entanglement witness for polarization entangled photons. It represents a recently discovered significant quantum information protocol which is based on few local measurements. The present demonstration has been applied to the so-called Werner states, a family of ''mixed'' quantum states that include both entangled and non entangled states. These states have been generated by a novel high brilliance source of entanglement which allows to continuously tune the degree of mixedness.

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M. Barbieri, F. De Martini, G. Di Nepi, P. Mataloni, G. M. D'Ariano, C. Macchiavello. 2003-07-01. Experimental Detection of Entanglement with Polarized Photons. https://doi.org/10.1103/physrevlett.91.227901

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