Experimental Certification of Nonclassicality via Phase-Space Inequalities
Authors: Biagi N., Bohmann M., Agudelo E., Bellini M., Zavatta A.
Autors Affiliation: Istituto Nazionale di Ottica (CNR-INO), L.go E. Fermi 6, 50125 Florence, Italy
LENS and Department of Physics & Astronomy, University of Firenze, 50019 Sesto Fiorentino, Florence, Italy
Institute for Quantum Optics and Quantum Information—IQOQI Vienna, Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna, Austria
Vienna Center for Quantum Science and Technology (VCQ), Vienna, Austria
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.
Journal/Review: PHYSICAL REVIEW LETTERS
Volume: 126 (2) Pages from: 023605-1 to: 023605-6
KeyWords: Optical tests of quantum theory, Quantum optics, Quantum states of light, Quantum tomographyDOI: https://doi.org/10.1103/PhysRevLett.126.023605