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arXiv · 1205.6195

Heralded processes on continuous-variable spaces as quantum maps

Franck Ferreyrol·Nicolò Spagnolo·Rémi Blandino·Marco Barbieri·Rosa Tualle-Brouri
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Abstract

Conditional evolution is crucial for generating non-Gaussian resources for quantum information tasks in the continuous variable scenario. However, tools are lacking for a convenient representation of heralded process in terms of quantum maps for continuous variable states, in the same way as Wigner functions are able to give a compact description of the quantum state. Here we propose and study such a representation, based on the introduction of a suitable transfer function to describe the action of a quantum operation on the Wigner function. We also reconstruct the maps of two relevant examples of conditional process, that is, noiseless amplification and photon addition, by combining experimental data and a detailed physical model. This analysis allows to fully characterize the effect of experimental imperfections in their implementations.

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Franck Ferreyrol, Nicolò Spagnolo, Rémi Blandino, Marco Barbieri, Rosa Tualle-Brouri. 2012-07-06. Heralded processes on continuous-variable spaces as quantum maps. https://doi.org/10.1103/physreva.86.062327

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