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arXiv · 1309.4221

Detecting quantum non-Gaussianity of noisy Schrödinger cat states

Mattia L. Palma·Jimmy Stammers·Marco G. Genoni·Tommaso Tufarelli·Stefano Olivares·M. S. Kim·Matteo G. A. Paris
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Abstract

Highly quantum non-linear interactions between different bosonic modes lead to the generation of quantum non-Gaussian states, i.e. states that cannot be written as mixtures of Gaussian states. A paradigmatic example is given by Schroedinger's cat states, that is coherent superpositions of coherent states with opposite amplitude. We here consider a novel quantum non-Gaussianity criterion recently proposed in the literature and prove its effectiveness on Schroedinger cat states evolving in a lossy bosonic channel. We prove that quantum non-Gaussianity can be effectively detected for high values of losses and for large coherent amplitudes of the cat states.

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Mattia L. Palma, Jimmy Stammers, Marco G. Genoni, Tommaso Tufarelli, Stefano Olivares, M. S. Kim, Matteo G. A. Paris. 2014-07-02. Detecting quantum non-Gaussianity of noisy Schrödinger cat states. https://doi.org/10.1088/0031-8949%2F2014%2Ft160%2F014035

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