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arXiv · 2008.08426

Multiphoton Bell-type inequality: a tool to unearth nonlocality of continuous variable quantum optical systems

Chandan Kumar·Gaurav Saxena·Arvind
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Abstract

We consider a multiphoton Bell-type inequality to study nonlocality in four-mode continuous variable systems, which goes beyond two-photon states and can be applied to mixed as well as states with fluctuating photon number. We apply the inequality to a wide variety of states such as pure and mixed Gaussian states (including squeezed thermal states) and non-Gaussian states. We consider beam splitters as a model for leakage and show that the inequality is able to detect nonclassicality of noisy Gaussian states as well. Finally, we investigate nonlocality in pair-coherent states and entangled coherent states, which are prominent examples of nonclassical, non-Gaussian states.

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Chandan Kumar, Gaurav Saxena, Arvind. 2020-08-19. Multiphoton Bell-type inequality: a tool to unearth nonlocality of continuous variable quantum optical systems. https://doi.org/10.1103/physreva.103.042224

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