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arXiv · 1710.03793

Nonclassicality and entanglement criteria for bipartite optical fields characterized by quadratic detectors

Jan Perina Jr·Ievgen I. Arkhipov·Vaclav Michalek·Ondrej Haderka
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Abstract

Numerous inequalities involving moments of integrated intensities and revealing nonclassicality and entanglement in bipartite optical fields are derived using the majorization theory, non-negative polynomials, the matrix approach, as well as the Cauchy-Schwarz inequality. Different approaches for deriving these inequalities are compared. Using the experimental photocount histogram generated by a weak noisy twin beam monitored by a photon-number-resolving iCCD camera the performance of the derived inequalities is compared. A basic set of ten inequalities suitable for monitoring the entanglement of a twin beam is suggested. Inequalities involving moments of photocounts (photon numbers) as well as those containing directly the elements of photocount (photon-number) distributions are also discussed as a tool for revealing nonclassicality.

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Jan Perina Jr, Ievgen I. Arkhipov, Vaclav Michalek, Ondrej Haderka. 2017-10-10. Nonclassicality and entanglement criteria for bipartite optical fields characterized by quadratic detectors. https://doi.org/10.1103/physreva.96.043845

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