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arXiv · 2407.18095

Detection of mode-intrinsic quantum entanglement

Carlos E. Lopetegui·Mathieu Isoard·Nicolas Treps·Mattia Walschaers
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Abstract

Quantum correlations are at the core of the power of quantum information and are necessary to reach a quantum computational advantage. In the context of continuous-variable quantum systems, another necessary ressource for quantum advantages is non-Gaussianity. In this work, we propose a witness, based on previously known relations between metrological power and quantum correlations, to detect a strong form of entanglement that only non-Gaussian states possess and that cannot be undone by passive optical operations, i.e., entanglement in all mode bases. The strength of our witness is two-fold: it only requires measurements in one basis to check entanglement in any arbitrary mode basis; it can be made applicable experimentally using homodyne measurements and without requiring a full tomography of the state.

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Carlos E. Lopetegui, Mathieu Isoard, Nicolas Treps, Mattia Walschaers. 2024-07-25. Detection of mode-intrinsic quantum entanglement. https://arxiv.org/abs/2407.18095

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