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arXiv · 2604.22295

Certification of genuine non-Gaussian entanglement

Abstract

Entanglement is a key resource for many quantum applications. Understanding fundamental properties of entangled states is an important step towards their practical exploitation. We characterize entanglement in the context of Gaussian and non-Gaussian processes and identify entangled states that cannot be produced by any Gaussian evolution acting on separable states. This distinction exposes intrinsic limitations of Gaussian operations and highlights the role of non-Gaussian operations as an important resource. We apply this framework to develop a certification method that connects entanglement theory with quantum non-Gaussianity - an advanced quantum feature that is essential for several quantum applications. Our approach tailors the certification to experimentally relevant states that can be produced in current quantum optics experiments. We demonstrate this certification for recognizing the genuine non-Gaussian entanglement of various entangled Fock states and hybrid entangled states.

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Lukáš Lachman, Carlos E. Lopetegui-González, Massimo Frigerio, Mattia Walschaers. 2026-04-24. Certification of genuine non-Gaussian entanglement. https://arxiv.org/abs/2604.22295

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