Extending loophole-free nonlocal correlations to arbitrarily large distances
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Published:2024-01-11
Issue:1
Volume:10
Page:
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ISSN:2056-6387
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Container-title:npj Quantum Information
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language:en
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Short-container-title:npj Quantum Inf
Author:
Chaturvedi AnubhavORCID,
Viola Giuseppe,
Pawłowski MarcinORCID
Abstract
AbstractQuantum theory allows spatially separated observers to share nonlocal correlations, which enable them to accomplish classically inconceivable information processing and cryptographic feats. However, the distances over which nonlocal correlations can be realized remain severely limited due to their high fragility to noise and high threshold detection efficiencies. To enable loophole-free nonlocality across large distances, we introduce Bell experiments wherein the spatially separated parties randomly choose the location of their measurement devices. We demonstrate that when devices close to the source are perfect and witness extremal nonlocal correlations, such correlations can be extended to devices placed arbitrarily far from the source. To accommodate imperfections close to the source, we demonstrate an analytic trade-off: the higher the loophole-free nonlocality close to the source, the lower the threshold requirements away from the source. We utilize this trade-off and formulate numerical methods to estimate the critical requirements of individual measurement devices in such experiments.
Funder
Narodowe Centrum Nauki
Institute of Information & Communications Technology Planning & Evaluation (IITP) grant funded by the Korean government (MSIT)
Fundacja na rzecz Nauki Polskiej
QuantERA, an ERA-Net co-fund in Quantum Technologies (www.quantera.eu), under project eDICT (contract No. Quantera/2/2020).
Publisher
Springer Science and Business Media LLC
Subject
Computational Theory and Mathematics,Computer Networks and Communications,Statistical and Nonlinear Physics,Computer Science (miscellaneous)
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