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IEEE/LEOS Summer Topical Meetings

Measurement of Fiber-Induced One-Way Noise Over Deployed Optical Links for Quantum Networks

Helena Zhang, Matthew E. Grein, Scott A. Hamilton, Isaac L. Chuang

Published Jul 1, 2018• 0 citations
Publisher

Abstract

Noise imparted to an optical signal propagating along a 42-km deployed optical fiber link is measured using two different techniques employing referenced mode-locked lasers. We compare the two techniques and assess their suitability for stabilizing the fiber link for quantum networks.
DOI
10.1109/phosst.2018.8456710

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We demonstrate the distribution of single-photon-level pulses from a mode-locked laser source over a phase-stable fiber link, achieving an optical timing jitter of less than 100 as over 10 minutes of data accumulation. This stability enables a fidelity greater than 0.998 between two stabilized 2.1 km long deployed fiber links. Building on time and frequency metrology techniques traditionally used for high-stability optical atomic clock signal distribution, we use time and frequency multiplexing to achieve an isolation of quantum and classical channels of 8×10 10 . Our results mark a necessary step towards scalable, high-rate quantum networks with a provable quantum advantage.
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