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arXiv · 2011.04320

Certification of non-Gaussian states with operational measurements

Ulysse Chabaud·Ganaël Roeland·Mattia Walschaers·Frédéric Grosshans·Valentina Parigi·Damian Markham·Nicolas Treps
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Abstract

We derive a theoretical framework for the experimental certification of non-Gaussian features of quantum states using double homodyne detection. We rank experimental non-Gaussian states according to the recently defined stellar hierarchy and we propose practical Wigner negativity witnesses. We simulate various use-cases ranging from fidelity estimation to witnessing Wigner negativity. Moreover, we extend results on the robustness of the stellar hierarchy of non-Gaussian states. Our results illustrate the usefulness of double homodyne detection as a practical measurement scheme for retrieving information about continuous variable quantum states.

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Ulysse Chabaud, Ganaël Roeland, Mattia Walschaers, Frédéric Grosshans, Valentina Parigi, Damian Markham, Nicolas Treps. 2020-11-09. Certification of non-Gaussian states with operational measurements. https://doi.org/10.1103/prxquantum.2.020333

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