在基于Ramsey作用的原子钟里，受限于原子的相干时间及晶振的相位噪声，自由演化时间不能太长。提出了大失谐光无破坏测量方法，利用该方法获取了原子相位数据，并将其反馈到微波相位上，从而实现了原子相位反馈，有效地延长了自由演化时间。分别从理论和实验上验证了这种周期性反馈作用的可行性。

In the atomic clocks based on the Ramsey process, the free evolution time cannot be very long which is limited by the coherent time of atoms and the phase noise of crystal oscillation. The non-destruction detection method with a large-detuning light is proposed. The atom phase data are obtained with this method and fed back to the microwave phase, which contributes to the realization of the atomic phase feedback and the effective prolonging of the free evolution time. The feasibility of such a periodical feedback is verified by the theory and experiment, respectively.