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arXiv · 2505.11303

Quantum Correlations in Three-Beam Symmetric Gaussian States Accessed via Photon-Number-Resolving Detection and Quantum Universal Invariants

Jan Peřina Jr.·Nazarii Sudak·Artur Barasiński·Antonín Černoch
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Abstract

Quantum correlations of 3-beam symmetric Gaussian states are analyzed using their quantum universal invariants. These invariants, 1-, 2-, and 3-beam purities, are expressed in terms of the beams' intensity moments up to sixth order. The 3-beam symmetric Gaussian states with varying amounts of the noise are experimentally generated using entangled photon pairs from down-conversion, their invariants are determined, and their quantum correlations are quantified. The coexistence of bi- and tripartite entanglement and genuine tripartite entanglement are observed in these states that resemble the noisy GHZ/W states.

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Jan Peřina Jr., Nazarii Sudak, Artur Barasiński, Antonín Černoch. 2025-05-16. Quantum Correlations in Three-Beam Symmetric Gaussian States Accessed via Photon-Number-Resolving Detection and Quantum Universal Invariants. https://arxiv.org/abs/2505.11303

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