Quantifying Two-Mode Entanglement of Bosonic Gaussian States from Their Full Counting Statistics
Phys. Rev. Lett. 135, 100201 – Published 5 September, 2025
DOI: https://doi.org/10.1103/1y1p-zqhh
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.