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arXiv · 2503.09555

Quantifying two-mode entanglement of bosonic Gaussian states from their full counting statistics

Victor Gondret·Clothilde Lamirault·Rui Dias·Charlie Leprince·Christoph I. Westbrook·David Clément·Denis Boiron
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Abstract

We study the entanglement properties of two-mode bosonic Gaussian states based on their multi-mode counting statistics. We exploit the idea that measuring high-order correlations of particle numbers can reveal entanglement without making any assumptions about the coherence of the fields. We show that the two- and four-body number correlations are sufficient to fully characterize the entanglement of two-mode bosonic Gaussian states for which each mode exhibits a thermal distribution. In addition, we derive an entanglement witness based on two-body correlations alone. Our findings are of great importance because it becomes possible to reveal entanglement in a series of recent experiments.

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Victor Gondret, Clothilde Lamirault, Rui Dias, Charlie Leprince, Christoph I. Westbrook, David Clément, Denis Boiron. 2025-03-12. Quantifying two-mode entanglement of bosonic Gaussian states from their full counting statistics. https://doi.org/10.1103/1y1p-zqhh

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