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arXiv · 2504.15831

Detecting strongly non-Gaussian entanglement

Serge Deside·Tobias Haas·Nicolas J. Cerf
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Abstract

Efficiently certifying non-Gaussian entanglement in continuous-variable quantum systems is a central challenge for advancing quantum information processing, photonic quantum computing, and metrology. Here, we put forward continuous-variable counterparts to the recently introduced entanglement criteria based on moments of the partially transposed state, together with simple readout schemes that require only a few replicas of the state, passive linear optics, and particle-number measurements. We develop a multicopy method that enables the detection of strongly non-Gaussian entanglement for various relevant state families overlooked by standard approaches, which include the entire class of NOON states. Further, it is robust against realistic experimental constraints (losses, noise, and finite statistics), which we demonstrate by extensive numerical simulations.

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Serge Deside, Tobias Haas, Nicolas J. Cerf. 2025-04-22. Detecting strongly non-Gaussian entanglement. https://doi.org/10.1103/297d-3tbj

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