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arXiv · 1403.6264

Quantum non-Gaussianity witnesses in the phase space

Catherine Hughes·Marco G. Genoni·Tommaso Tufarelli·Matteo G. A. Paris·M. S. Kim
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Abstract

We address detection of quantum non-Gaussian states, i.e. nonclassical states that cannot be expressed as a convex mixture of Gaussian states, and present a method to derive a new family of criteria based on generic linear functionals. We then specialise this method to derive witnesses based on $s$-parametrized quasiprobability functions, generalising previous criteria based on the Wigner function. In particular we discuss in detail and analyse the properties of Husimi Q-function based witnesses and prove that they are often more effective than previous criteria in detecting quantum non-Gaussianity of various kinds of non-Gaussian states evolving in a lossy channel.

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Catherine Hughes, Marco G. Genoni, Tommaso Tufarelli, Matteo G. A. Paris, M. S. Kim. 2014-06-17. Quantum non-Gaussianity witnesses in the phase space. https://doi.org/10.1103/physreva.90.013810

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