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arXiv · 1206.7057

Experimental test of strongly non-classical character of a noisy squeezed single-photon state

M. Jezek·A. Tipsmark·R. Dong·J. Fiurasek·L. Mista Jr·R. Filip·U. L. Andersen
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Abstract

We experimentally verify the quantum non-Gaussian character of a conditionally generated noisy squeezed single-photon state with positive Wigner function. Employing an optimized witness based on probabilities of squeezed vacuum and squeezed single-photon states we prove that the state cannot be expressed as a mixture of Gaussian states. In our experiment, the non-Gaussian state is generated by conditional subtraction of a single photon from squeezed vacuum state. The state is probed with a homodyne detector and the witness is determined by averaging a suitable pattern function over the measured homodyne data. Our experimental results are in good agreement with a theoretical fit obtained from a simple yet realistic model of the experimental setup.

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M. Jezek, A. Tipsmark, R. Dong, J. Fiurasek, L. Mista Jr, R. Filip, U. L. Andersen. 2012-06-29. Experimental test of strongly non-classical character of a noisy squeezed single-photon state. https://doi.org/10.1103/physreva.86.043813

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