Work

Absolute clock synchronization with a single time-correlated photon pair source over a 10 km optical fibre

Year: 2022

Type: article

Abstract: We demonstrate a point-to-point clock synchronization protocol based on bidirectionally propagating photons generated in a single spontaneous parametric down-conversion (SPDC) source. Tight timing correlations between photon pairs are used to determine the single and round-trip times measured by two separate clocks, providing sufficient information for distance-independent absolute synchronization secure against symmetric delay attacks. We show that the coincidence signature useful for determining the round-trip time of a synchronization channel, established using a 10 km telecommunications fiber, can be derived from photons reflected off the end face of the fiber without additional optics. Our technique allows the synchronization of multiple clocks with a single reference clock co-located with the source, without requiring additional pair sources, in a client-server configuration suitable for synchronizing a network of clocks.

Source: Optics Express

DOI: 10.1364/oe.455542

Authors: Jianwei Lee, Lijiong Shen, Adrian Nugraha Utama, Christian Kurtsiefer

Institutions: Centre for Quantum Technologies, National University of Singapore

Language: English

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,270

Funders: National Research Foundation, Ministry of Education - Singapore