Optimization of frequency shifts in optically detected magnetic-state-selection cesium beam atomic clocks

In this paper, we report a new method to suppress the AC Stark effect (light shift) in compact cesium beam atomic clocks. The clock used in experiment uses the optically detected magnetic-state-selection scheme independently proposed and developed by Peking University. This method compensates the AC Stark effect by introducing a detuned laser into the detection light. We demonstrate theoretically that the AC Stark effect can be strongly suppressed with properly chosen detuned light. In addition, we experiment this scheme and the a-coefficient (the sensitivity of the AC Stark effect to laser power fluctuation) is successfully reduced from 1.23 x 10(-12) /mW to 8 x 10(-14)/mW. We also test the long-term frequency stability with additional laser intensity noise. It is shown that the fractional Allan deviation at 20000 s is reduced from 2.0 x 10(-13) to 5.9 x 10(-14), which reveals the suppression of the light shift with our method. These results are relevant for improving the long-term frequency stability of compact cesium beam atomic clocks. Copyright (C) 2022 EPLA