Low Phase Noise Microwave Synthesizer for Coherent Population Trapping Atomic Clock
YAO Ming-hao1,DUAN Jun-yi2,WANG Xue-ying1,HAN Qi-na2,SHI Yang2,ZHOU Kun-li2,RU Ning2,LIU Xiao-chi2,QU Ji-feng2
1.College of Metrology and Measurement Engineering, China Jiliang University, Hangzhou, Zhejiang 310018, China
2.Center for Advanced Measurement Science, National Institute of Metrology, Beijing 102200, China
Abstract：Atomic clock based on coherent population trapping (CPT) could interrogate the atoms without microwave cavity, which significantly reduce the volume of the physical package. One of the main limitations of CPT clock is the phase noise of the microwave synthesizer. Here a low phase nosie microwave synthesizer for CPT clock system is demonstrated. The absolute phase noise of the microwave synthesizer achieved -108dBc/Hz at 200Hz offset frequency. The frequency stability limitation of CPT clock with this synthesizer is calculated to be 8. 2×10-14 with Dick effect formula. This low phase noise microwave synthesizer could be also applied in other types of precision measurement system and standards based on atoms.
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2022, Vol. 43 
