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arXiv · 1505.06089

Unified nonclassicality criteria

Sergej Ryl·Jan Sperling·Elizabeth Agudelo·Melanie Mraz·Semjon Köhnke·Boris Hage·Werner Vogel
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Abstract

In this work we generalize the Bochner criterion addressing the characteristic function, i.e., the Fourier transform, of the Glauber-Sudarshan phase-space function. For this purpose we extend the Bochner theorem by including derivatives of the characteristic function. The resulting necessary and sufficient nonclassicality criteria unify previously known moment-based criteria with those based on the characteristic function. For applications of the generalized nonclassicality probes, we provide direct sampling formulas for balanced homodyne detection. A squeezed vacuum state is experimentally realized and characterized with our method. This complete framework -- theoretical unification, sampling approach, and experimental implementation -- presents an efficient toolbox to characterize quantum states of light for applications in quantum technology.

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Sergej Ryl, Jan Sperling, Elizabeth Agudelo, Melanie Mraz, Semjon Köhnke, Boris Hage, Werner Vogel. 2015-07-22. Unified nonclassicality criteria. https://doi.org/10.1103/physreva.92.011801

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