Abstract：The atomic clock based on coherent population beating (CPB) phenomenon can directly obtain the frequency difference and its shift of an atom transition frequency and a microwave frequency. In order to solve the problem of signal amplitude decay in asynchronous CPB scheme, the scheme of synchronously stimulated CPB atomic clock is proposed. By synchronously applying two coherent population trapping (CPT) resonant stimulating lights and two detuned detecting lights to an atomic cell, the coherence of atomic ground states can be maintained, and the CPB signal will not decay. The continuous CPB signal is beneficial for the accuracy of and the stability of atomic clock. The table experimental system of the synchronously stimulated CPB clock had achieved the stability of 7.7×10-11 at 1 second, 9.6×10-13 at 1000 second.
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2015, Vol. 36 
