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arXiv · 2010.00259

Experimental certification of nonclassicality via phase-space inequalities

Nicola Biagi·Martin Bohmann·Elizabeth Agudelo·Marco Bellini·Alessandro Zavatta
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Abstract

In spite of its fundamental importance in quantum science and technology, the experimental certification of nonclassicality is still a challenging task, especially in realistic scenarios where losses and noise imbue the system. Here, we present the first experimental implementation of the recently introduced phase-space inequalities for nonclassicality certification, which conceptually unite phase-space representations with correlation conditions. We demonstrate the practicality and sensitivity of this approach by studying nonclassicality of a family of noisy and lossy quantum states of light. To this end, we experimentally generate single-photon-added thermal states with various thermal mean photon numbers and detect them at different loss levels. Based on the reconstructed Wigner and Husimi Q functions, the inequality conditions detect nonclassicality despite the fact that the involved distributions are nonnegative, which includes cases of high losses (93%) and cases where other established methods do not reveal nonclassicality. We show the advantages of the implemented approach and discuss possible extensions that assure a wide applicability for quantum science and technologies.

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Nicola Biagi, Martin Bohmann, Elizabeth Agudelo, Marco Bellini, Alessandro Zavatta. 2020-10-01. Experimental certification of nonclassicality via phase-space inequalities. https://doi.org/10.1103/physrevlett.126.023605

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