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Frequency shift mitigation in a cold-atom CPT clock



Xiaochi Liu, John Kitching, Elizabeth Donley, Eugene N. Ivanov


An upgrade in the laser interrogation system for our cold-atom clock based on coherent population trapping has resulted in a reduced light shift. The new approach makes use of an electro-optic modulator to significantly reduce the phase coherence of the interrogation spectrum relative to what was achieved with our previous phase-locked loop approach. We present the impact of this improvement on the performance of the clock, for which the light shift was previously dominated by the incoherent light in the laser spectrum.
Proceedings Title
2016 IEEE International Frequency Control Symposium
Conference Dates
May 9-13, 2016
Conference Location
New Orleans, LA, US


Phase-locked loop, coherent population trapping, light shift, AC Stark Shift, electro-optic modulator


Liu, X. , Kitching, J. , Donley, E. and Ivanov, E. (2016), Frequency shift mitigation in a cold-atom CPT clock, 2016 IEEE International Frequency Control Symposium, New Orleans, LA, US, [online], (Accessed March 2, 2024)
Created May 8, 2016, Updated April 19, 2022