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arXiv · 1404.1422

Experimental semi-device-independent certification of entangled measurements

Adam Bennet·Tamás Vértesi·Dylan J. Saunders·Nicolas Brunner·G. J. Pryde
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Abstract

Certifying the entanglement of quantum states with Bell inequalities allows one to guarantee the security of quantum information protocols independently of imperfections in the measuring devices. Here we present a similar procedure for witnessing entangled measurements, which play a central role in many quantum information tasks. Our procedure is termed semi-device-independent, as it uses uncharacterized quantum preparations of fixed Hilbert space dimension. Using a photonic setup, we experimentally certify an entangled measurement using measurement statistics only. We also apply our techniques to certify unentangled but nevertheless inherently quantum measurements.

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Adam Bennet, Tamás Vértesi, Dylan J. Saunders, Nicolas Brunner, G. J. Pryde. 2014-04-05. Experimental semi-device-independent certification of entangled measurements. https://doi.org/10.1103/physrevlett.113.080405

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