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arXiv · 2412.16973

Experimental quantum randomness enhanced by a quantum network

Emanuele Polino·Luis Villegas-Aguilar·Davide Poderini·Nathan Walk·Farzad Ghafari·Marco Túlio Quintino·Alexey Lyasota·Sven Rogge·Rafael Chaves·Geoff J. Pryde·Eric G. Cavalcanti·Nora Tischler·Sergei Slussarenko
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Abstract

The certification of randomness is essential for both fundamental science and information technologies. Unlike traditional random number generators, randomness obtained from nonlocal correlations is fundamentally guaranteed to be unpredictable. However, it is also highly susceptible to noise. Here, we show that extending the conventional bipartite Bell scenario to hybrid quantum networks -- which incorporate both quantum channels and entanglement sources -- enhances the robustness of certifiable randomness. Our protocol even enables randomness to be certified from Bell-local states, broadening the range of quantum states useful for this task. Through both theoretical analysis and experimental validation in a photonic network, we demonstrate enhanced performance and improved noise resilience.

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Emanuele Polino, Luis Villegas-Aguilar, Davide Poderini, Nathan Walk, Farzad Ghafari, Marco Túlio Quintino, Alexey Lyasota, Sven Rogge, Rafael Chaves, Geoff J. Pryde, Eric G. Cavalcanti, Nora Tischler, Sergei Slussarenko. 2024-12-22. Experimental quantum randomness enhanced by a quantum network. https://arxiv.org/abs/2412.16973

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