Nonlocality activation in a photonic quantum network - Archive ouverte HAL Access content directly
Journal Articles Nature Communications Year : 2023

Nonlocality activation in a photonic quantum network

Luis Villegas-Aguilar
Farzad Ghafari
Marco Túlio Quintino
Ian Berkman
Sven Rogge
Lynden Shalm
  • Function : Author
Nora Tischler
Sergei Slussarenko
Geoff Pryde


Bell nonlocality refers to correlations between two distant, entangled particles that challenge classical notions of local causality. Beyond its foundational significance, nonlocality is crucial for device-independent technologies like quantum key distribution and randomness generation. Nonlocality quickly deteriorates in the presence of noise, and restoring nonlocal correlations requires additional resources. These often come in the form of many instances of the input state and joint measurements, incurring a significant resource overhead. Here, we experimentally demonstrate that single copies of Bell-local states, incapable of violating any standard Bell inequality, can give rise to nonlocality after being embedded into a quantum network of multiple parties. We subject the initial entangled state to a quantum channel that broadcasts part of the state to two independent receivers and certify the nonlocality in the resulting network by violating a tailored Bell-like inequality. We obtain these results without making any assumptions about the prepared states, the quantum channel, or the validity of quantum theory. Our findings have fundamental implications for nonlocality and enable the practical use of nonlocal correlations in real-world applications, even in scenarios dominated by noise.

Dates and versions

hal-04209369 , version 1 (17-09-2023)



Luis Villegas-Aguilar, Emanuele Polino, Farzad Ghafari, Marco Túlio Quintino, Kiarn Laverick, et al.. Nonlocality activation in a photonic quantum network. Nature Communications, 2023, pp.3112. ⟨10.1038/s41467-024-47354-w⟩. ⟨hal-04209369⟩
29 View
0 Download



Gmail Mastodon Facebook X LinkedIn More