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
@article{arxiv.1501.02403,
title = {Non-Gaussian state generation certified using the EPR-steering inequality},
author = {E. S. Gómez and G. Cañas and E. Acuña and W. A. T. Nogueira and G. Lima},
journal= {arXiv preprint arXiv:1501.02403},
year = {2015}
}