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arXiv · 1003.2799

Sub-100 attoseconds optics-to-microwave synchronization

W. Zhang·Z. Xu·M. Lours·R. Boudot·Y. Kersale·G. Santarelli·Y. Le Coq
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Abstract

We use two fiber-based femtosecond frequency combs and a low-noise carrier suppression phase detection system to characterize the optical to microwave synchronization achievable with such frequency divider systems. By applying specific noise reduction strategies, a residual phase noise as low as -120 dBc/Hz at 1 Hz offset frequency from a 11.55 GHz carrier is measured. The fractional frequency instability from a single optical-to-frequency divider is 1.1E-16 at 1 s averaging down to below 2E-19 after only 1000 s. The corresponding rms time deviation is lower than 100 attoseconds up to 1000 s averaging duration.

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W. Zhang, Z. Xu, M. Lours, R. Boudot, Y. Kersale, G. Santarelli, Y. Le Coq. 2010-03-14. Sub-100 attoseconds optics-to-microwave synchronization. https://doi.org/10.1063/1.3431299

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