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arXiv · 1609.07336

Entanglement and nonclassicality in four-mode Gaussian states generated via parametric down-conversion and frequency up-conversion

Ievgen I. Arkhipov·Jan Peřina Jr.·Ondřej Haderka·Alessia Allevi·Maria Bondani
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Abstract

Multipartite entanglement and nonclassicality of four-mode Gaussian states generated in two simultaneous nonlinear processes involving parametric down-conversion and frequency up-conversion are analyzed assuming the vacuum as the initial state. Suitable conditions for the generation of highly entangled states are found. Transfer of the entanglement from the down-converted modes into the up-converted ones is also suggested. The analysis of the whole set of states reveals that sub-shot-noise intensity correlations between the equally-populated down-converted modes, as well as the equally-populated up-converted modes, uniquely identify entangled states. They represent a powerful entanglement identifier also in other cases with arbitrarily populated modes.

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Ievgen I. Arkhipov, Jan Peřina Jr., Ondřej Haderka, Alessia Allevi, Maria Bondani. 2016-09-23. Entanglement and nonclassicality in four-mode Gaussian states generated via parametric down-conversion and frequency up-conversion. https://doi.org/10.1038/srep33802

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