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arXiv · 1609.09731

Experimental nonlocality-based network diagnostics of mutipartite entangled states

Mario A. Ciampini·Caterina Vigliar·Valeria Cimini·Stefano Paesani·Fabio Sciarrino·Andrea Crespi·Giacomo Corrielli·Roberto Osellame·Paolo Mataloni·Mauro Paternostro·Marco Barbieri
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Abstract

Quantum networks of growing complexity play a key role as resources for quantum computation; the ability to identify the quality of their internal correlations will play a crucial role in addressing the buiding stage of such states. We introduce a novel diagnostic scheme for multipartite networks of entangled particles, aimed at assessing the quality of the gates used for the engineering of their state. Using the information gathered from a set of suitably chosen multiparticle Bell tests, we identify conditions bounding the quality of the entangled bonds among the elements of a register. We demonstrate the effectiveness, flexibility, and diagnostic power of the proposed methodology by characterizing a quantum resource engineered combining two-photon hyperentanglement and photonic-chip technology. Our approach is feasible for medium-sized networks due to the intrinsically modular nature of cluster states, and paves the way to section-by-section analysis of large photonics resources.

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Mario A. Ciampini, Caterina Vigliar, Valeria Cimini, Stefano Paesani, Fabio Sciarrino, Andrea Crespi, Giacomo Corrielli, Roberto Osellame, Paolo Mataloni, Mauro Paternostro, Marco Barbieri. 2016-09-30. Experimental nonlocality-based network diagnostics of mutipartite entangled states. https://doi.org/10.1038/s41598-017-17457-0

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