An Yb-fiber frequency comb phase-locked to microwave standard and optical reference<xref rid="cpb_29_3_030601fn1" ref-type="fn">*</xref><fn id="cpb_29_3_030601fn1"><label>*</label><p>Project supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant Nos. XDA1502040404 and XDB21010400) and the National Natural Science Foundation of China (Grant Nos. 91850209 and 11774234).</p></fn>

An Yb-fiber frequency comb phase-locked to microwave standard and optical reference**

Project supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant Nos. XDA1502040404 and XDB21010400) and the National Natural Science Foundation of China (Grant Nos. 91850209 and 11774234).

Wang Hui-Bo^{1, 2}, Han Hai-Nian^{2, 3, †}, Zhang Zi-Yue^{2, 3}, Shao Xiao-Dong^{2, 3}, Zhu Jiang-Feng¹, Wei Zhi-Yi^{1, 2, 3}

Long-term frequency shift and Allan deviation of the comb locked to an RF reference. (a) Residual fluctuations of the f_ceo signal with a 1 s gate. The standard deviation for f_ceo is 6 mHz. (b) Residual fluctuations of the f_rep signal with a 1 s gate. The standard deviation for f_rep is 1 mHz. (c) Allan deviation normalized to the 20 MHz standard and optical frequency. (d) Allan deviation of the repetition rate.