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arXiv · 1807.04956

Self-testing entangled measurements in quantum networks

Marc-Olivier Renou·Jędrzej Kaniewski·Nicolas Brunner
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Abstract

Self-testing refers to the possibility of characterizing an unknown quantum device based only on the observed statistics. Here we develop methods for self-testing entangled quantum measurements, a key element for quantum networks. Our approach is based on the natural assumption that separated physical sources in a network should be considered independent. This provides a natural formulation of the problem of certifying entangled measurements. Considering the setup of entanglement swapping, we derive a robust self-test for the Bell-state measurement, tolerating noise levels up to 5%. We also discuss generalizations to other entangled measurements.

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Marc-Olivier Renou, Jędrzej Kaniewski, Nicolas Brunner. 2018-07-13. Self-testing entangled measurements in quantum networks. https://doi.org/10.1103/physrevlett.121.250507

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