A low phase noise microwave source for high performance CPT Rb atomic clock
Abstract
Phase noise of the frequency synthesizer is one of the main limitations to the short-term stability of microwave atomic clocks. In this work, we demonstrated a low-noise, simple-architecture microwave frequency synthesizer for a coherent population trapping (CPT) clock. The synthesizer is mainly composed of a 100 MHz oven controlled crystal oscillator (OCXO), a microwave comb generator and a direct digital synthesizer (DDS). The absolute phase noises of 3.417 GHz signal are measured to be -55 dBc/Hz, -81 dBc/Hz, -111 dBc/Hz and -134 dBc/Hz, respectively, for 1 Hz, 10 Hz, 100 Hz and 1 kHz offset frequencies, which shows only 1 dB deterioration at the second harmonic of the modulation frequency of the atomic clock. The estimated frequency stability of intermodulation effect is 4.7*10^{-14} at 1s averaging time, which is about half order of magnitude lower than that of the state-of-the-art CPT Rb clock. Our work offers an alternative microwave synthesizer for high-performance CPT Rb atomic clock.
Keywords
Cite
@article{arxiv.2103.02129,
title = {A low phase noise microwave source for high performance CPT Rb atomic clock},
author = {Xiaodong Li and Peter Yun and Qinglin Li and Bowen Ju and Shaoshao Yu and Qiang Hao and Runchang Du and Feng Xu and Wenbing Li and Yuping Gao and Shougang Zhang},
journal= {arXiv preprint arXiv:2103.02129},
year = {2021}
}
Comments
3 pages, 5 figures, 1 table