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arXiv · 2312.10459

Time-interval Measurement with Linear Optical Sampling at the Femtosecond Level

Abstract

High-precision time-interval measurement is a fundamental technique in many advanced applications, including time and distance metrology, particle physics, and ultra-precision machining. However, many of these applications are confined by the imprecise time-interval measurement of electrical signals, restricting the performance of the ultimate system to a few picoseconds, which limits ultra-high-precision applications. Here, we demonstrate an optical means of the time-interval measurement of electrical signals that can successfully achieve femtosecond (fs)-level precision. The setup is established using the optical-frequency-comb (OFC)-based linear optical sampling technique to realize timescale-stretched measurement. We achieve the measurement precision of 82 fs for a single LOS scan measurement and 3.05 fs for the 100-times average with post-processing, which is three orders of magnitude higher than the results of older electrical methods. The high-precision time interval measurement of electrical signals can substantially improve precision measurement technologies.

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Dongrui Yu, Ziyang Chen, Xuan Yang, Yunlong Xu, Ziyi Jin, Panxue Ma, Yufei Zhang, Song Yu, Bin Luo, Hong Guo. 2023-12-16. Time-interval Measurement with Linear Optical Sampling at the Femtosecond Level. https://doi.org/10.1364/prj.498810

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