A simplified and efficient method of laser frequency shifting and power stabilization

To overcome the shortcomings of large losses and fluctuations in the power of output beam during the independent control of the frequency shift and power stabilization in the current cold atom interferometer, a new combined control method of laser frequency shift and power stabilization is proposed. The proposed method is based on the fact that the frequency shift and power stabilization are controlled by different control parameters of the acousto-optic modulator. Only one acousto-optic modulator is used to realize the two functions, which reduces the number of optical components and the power loss in the optical path, especially the number of acousto-optic modulators. Moreover, the proposed method can simultaneously adjust the frequency and power of the output beam through preprocessing of acousto-optic modulator drive signal, which significantly reduces the effect of the frequency shift on the stability of the output beam power. Compared with the existing independent control method, the new method reduces the loss of the output beam power by 10.6%, the RMS (root-mean-square) stability by a factor of six, and the overshoot by a factor of three. The new method not only significantly improves the optical utilization rate and the stability of the output beam power, but also contributes to the miniaturization of the laser system in the cold atom interferometer (CAI).