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arXiv · 1812.08450

Symmetrical clock synchronization with time-correlated photon pairs

Jianwei Lee·Lijiong Shen·Alessandro Cerè·James Troupe·Antia Lamas-Linares·Christian Kurtsiefer
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Abstract

We demonstrate a point-to-point clock synchronization protocol based on bidirectionally exchanging photons produced in spontaneous parametric down conversion (SPDC). The technique exploits tight timing correlations between photon pairs to achieve a precision of 51ps in 100s with count rates of order 200s$^{-1}$. The protocol is distance independent, secure against symmetric delay attacks and provides a natural complement to techniques based on Global Navigation Satellite Systems (GNSS). The protocol works with mobile parties and can be augmented to provide authentication of the timing signal via a Bell inequality check.

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Jianwei Lee, Lijiong Shen, Alessandro Cerè, James Troupe, Antia Lamas-Linares, Christian Kurtsiefer. 2018-12-20. Symmetrical clock synchronization with time-correlated photon pairs. https://doi.org/10.1063/1.5086493

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