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arXiv · 0812.3015

Experimental test of nonclassicality criteria

T. Kiesel·W. Vogel·B. Hage·J. DiGuglielmo·A. Samblowski·R. Schnabel
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Abstract

We experimentally examine the nonclassical character of a class of non-Gaussian states known as phase-diffused squeezed states. These states may show no squeezing effect at all, and therefore provide an interesting example to test nonclassicality criteria. The characteristic function of the Glauber-Sudarshan representation (P function) proves to be a powerful tool to detect nonclassicality. Using this criterion we find that phase-diffused squeezed states are always nonclassical, even if the squeezing effect vanishes. Testing other criteria of nonclassicality based on higher-order squeezing and the positive semidefinitness of special matrices of normally ordered moments, it is found that these criteria fail to reveal the nonclassicality for some of the prepared phase-diffused squeezed states.

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T. Kiesel, W. Vogel, B. Hage, J. DiGuglielmo, A. Samblowski, R. Schnabel. 2008-12-16. Experimental test of nonclassicality criteria. https://doi.org/10.1103/physreva.79.022122

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