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arXiv · 1105.3138

Device-independent certification of entangled measurements

Rafael Rabelo·Melvyn Ho·Daniel Cavalcanti·Nicolas Brunner·Valerio Scarani
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Abstract

We present a device-independent protocol to test if a given black-box measurement device is entangled, that is, has entangled eigenstates. Our scheme involves three parties and is inspired by entanglement swapping; the test uses the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality, checked between each pair of parties. Also, focusing on the case where all particles are qubits, we characterize quantitatively the deviation of the measurement device from a perfect Bell state measurement.

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Rafael Rabelo, Melvyn Ho, Daniel Cavalcanti, Nicolas Brunner, Valerio Scarani. 2011-05-16. Device-independent certification of entangled measurements. https://doi.org/10.1103/physrevlett.107.050502

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