The ultra-stable microwave based on ultra-stable laser with Robustness and Long-Term Stability

摘要

The ultra-stable microwave (USM) based on ultra-stable laser (USL) and fiber optical frequency comb (OFC) is built at the National Institute of Metrology (NIM), China. The OFC is stabilized with USL by controlling the pumping current and piezoelectric transducer (PZT). Meanwhile, the error signal is send to the temperature control of the optical resonant cavity for the long term locking which enable a more than 30 days continuously running. The second stability is 4E-15. By controlling the driving frequency of the AOM, the long term stability of H master is transmitted to the USM. This USM will be applied as the local oscillator for NIM5 Cs fountain to improve its short term stability.