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arXiv · 2209.09921

Partial self-testing and randomness certification in the triangle network

Pavel Sekatski·Sadra Boreiri·Nicolas Brunner
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Abstract

Quantum nonlocality can be demonstrated without inputs (i.e. each party using a fixed measurement setting) in a network with independent sources. Here we consider this effect on ring networks, and show that the underlying quantum strategy can be partially characterized, or self-tested, from observed correlations. Applying these results to the triangle network allows us to show that the nonlocal distribution of Renou et al. [Phys. Rev. Lett. 123, 140401 (2019)] requires that (i) all sources produce a minimal amount of entanglement, (ii) all local measurements are entangled, and (iii) each local outcome features a minimal entropy. Hence we show that the triangle network allows for genuine network quantum nonlocality and certifiable randomness.

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Pavel Sekatski, Sadra Boreiri, Nicolas Brunner. 2022-09-20. Partial self-testing and randomness certification in the triangle network. https://doi.org/10.1103/physrevlett.131.100201

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