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arXiv · 2007.08310

Experimental quantification of the entanglement of noisy twin beams

Vaclav Michalek·Jan Perina Jr.·Ondrej Haderka
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Abstract

Gradual loss of the entanglement of a twin beam containing around 25 photon pairs with the increasing external noise is experimentally investigated. The entanglement is quantified by the non-classicality depths and the non-classicality counting parameters related to several non-classicality criteria. The reduction of intensity moments of the analyzed multi-mode twin beams to single-mode ones allows to determine the negativity as another quantifier of the entanglement. Both the raw photocount histograms and the reconstructed photon-number distributions are analyzed in parallel.

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Vaclav Michalek, Jan Perina Jr., Ondrej Haderka. 2020-07-16. Experimental quantification of the entanglement of noisy twin beams. https://doi.org/10.1103/physrevapplied.14.024003

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