冷原子干涉仪探测激光功率稳定系统实验研究

Probe Laser Power Stabilization System for Cold Atom Interferometer

为降低探测激光功率抖动对高精度冷原子干涉仪测量结果的影响,以声光调制器作为激光强度反馈媒介,采用混频器对声光调制器驱动射频功率进行控制,搭建了用于冷原子干涉仪探测激光脉冲的功率稳定系统,实现了冷原子干涉仪探测过程中激光脉冲的快速功率稳定。功率稳定后,激光脉冲的功率稳定建立时间达到μs量级,功率稳定度优于2.11×10^(-4)(500μs),激光功率的长期稳定度为2.47×10^(-4)(14 h),激光功率的噪声得到了有效抑制。理论上可以将探测激光的功率抖动对于冷原子干涉仪相位信号的噪声贡献降低至1.38 mrad。较大程度上提高了干涉信号的稳定性,降低了系统噪声。

In order to reduce the impact of the probe laser power jitter on the measurement results of the high-precision cold atom interferometer,the acousto-optic modulator is used as the laser intensity feedback medium,and a mixer is used to control the radio frequency power which driving the acousto-optic modulator.By the power stabilization experimental system of the probe laser pulses,it can achieve the rapid power stabilization of the laser pulse during the detection process of the cold atom interferometer.When the power is stabilized,the power stability established time of the laser pulse is on the order of microseconds(us),the power stability is better than 2.11×10^(-4)(within 500μs),and the long-term stability of the laser power is about 2.47×10^(-4)(in 14 hours),so the power noise of the laser can be effectively suppressed.Theoretically,the influence of the power noise of the probe laser on the interferencephase of the cold atom interferometer can be reduced to 1.38 mrad.The stability of interference signal is improved to a great entent and the system noise is also reduced.