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.
@article{arxiv.1710.03793,
title = {Nonclassicality and entanglement criteria for bipartite optical fields characterized by quadratic detectors},
author = {Jan Perina and Ievgen I. Arkhipov and Vaclav Michalek and Ondrej Haderka},
journal= {arXiv preprint arXiv:1710.03793},
year = {2018}
}