激光泵浦的铯-氦磁力仪的信号特征

Signal Characteristics of the Laser-pumped Cesium-Helium Magnetometer

研究了基于激光泵浦的铯-氦磁力仪的磁共振信号特征。通过使用窄线宽激光对铯原子进行泵浦,得到了12.3 A/T的电流-磁场转换因子,与基于放电灯泵浦的铯-氦磁力仪相比,转化效率增大13.5倍。实验发现通过间接泵浦,可消除“光致展宽”。通过分析线宽的实验值和理论值,得到实验值线宽的最大展宽来自于脉冲激励的结论。通过测量光源、磁场、光电传感器和电路的本底噪声,确定了该磁力仪最大的噪声源为光源和磁场,以磁场分辨力为优化目标得到了最佳光强,铯-氦磁力仪的磁场分辨力可以达到0.05 nT。

The magnetic resonance signal characteristics of cesium-helium magnetometer(CHM)based on laser pumping was studied.By pumping cesium atoms with a narrow-line-width laser,the magnetometer achieved 12.3 A/T current-magnetic field conversion efficiency,which is 13.5 times greater than the CHM based on the discharge lamp pumping.The“power broadening”was eliminated by indirect pumping.By analyzing the data and the theoretical value of the line width,it was concluded that the maximum broadening factor comes from the pulsed excitation.By measuring the background noise of the light source,magnetic field,photoelectric sensor and circuit,the largest noise source of the magnetometer was determined to be the light source and magnetic field,and the optimal light intensity was obtained by taking the magnetic field resolution as the optimization target.The magnetic field resolution of the cesium-helium magnetometer can reach 0.05 nT.