基于DDS+PLL的光源调制与功率稳定控制方法

Light Source Modulation and Power Stability Control Method Based on DDS+PLL

量子传感器是基于量子操控技术的研究成果,一般具有高精度、小体积等优势。激光器是量子传感器的核心部件,有抽运和检测功能,激光器的稳定性对量子传感器具有重要的意义。提出了一种直接数字合成法(DDS)与锁相回路(PLL)相结合的方法,对激光器进行调制并抑制调制噪声,实现了激光器的稳定输出。基于现有小型量子传感器装置,在DDS生成4kHz参考信号的情况下实现了激光器电流8kHz调制,抑制了调制时调制电流信号噪声约8dB,并提高了激光器输出光功率的稳定性。

Quantum sensors are research results based on quantum control technology, and generally have the advantages of high precision, small size and so on. Lasers are core components of quantum sensors, which have pumping and detection functions. The stability of laser is of great significance to quantum sensors. In this paper, a combination method of direct digital synthesis(DDS) and phase locked loop(PLL) is proposed to perform frequency modulation and suppress modulation noise to achieve stable output of laser. In this paper, based on the existing small quantum sensor device, a 8 kHz laser current modulation is realized under the condition that DDS generates a 4 kHz reference signal, and the noise of modulation current signal is suppressed by about 8 dB, and the stability of laser light intensity output is improved.