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arXiv · 1501.02403

Non-Gaussian state generation certified using the EPR-steering inequality

E. S. Gómez·G. Cañas·E. Acuña·W. A. T. Nogueira·G. Lima
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Abstract

Due to practical reasons, experimental and theoretical continuous-variable (CV) quantum information (QI) has been heavily based on Gaussian states. Nevertheless, many CV-QI protocols require the use of non-Gaussian states and operations. Here, we show that the Einstein-Podolsky-Rosen steering inequality can be used to obtain a practical witness for the generation of pure bipartite non-Gaussian states. While the scenario require pure states, we show its broad relevance by reporting the experimental observation of the non-Gaussianity of the CV two-photon state generated in the process of spontaneous parametric down-conversion (SPDC). The observed non-Gaussianity is due only to the intrinsic phase-matching conditions of SPDC

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E. S. Gómez, G. Cañas, E. Acuña, W. A. T. Nogueira, G. Lima. 2015-01-10. Non-Gaussian state generation certified using the EPR-steering inequality. https://doi.org/10.1103/physreva.91.013801

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