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arXiv · 0804.1016

Experimental determination of a nonclassical Glauber-Sudarshan P function

T. Kiesel·W. Vogel·V. Parigi·A. Zavatta·M. Bellini
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Abstract

A quantum state is nonclassical if its Glauber-Sudarshan P function fails to be interpreted as a probability density. This quantity is often highly singular, so that its reconstruction is a demanding task. Here we present the experimental determination of a well-behaved P function showing negativities for a single-photon-added thermal state. This is a direct visualization of the original definition of nonclassicality. The method can be useful under conditions for which many other signatures of nonclassicality would not persist.

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T. Kiesel, W. Vogel, V. Parigi, A. Zavatta, M. Bellini. 2008-08-28. Experimental determination of a nonclassical Glauber-Sudarshan P function. https://doi.org/10.1103/physreva.78.021804

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