Abstract Optical pumping is a process that produces a nonthermal Zeeman sublevel population distribution. It plays an important role in alkali-metal magnetometers for two uses, constructing the sub-Doppler features to lock the laser frequency and providing the spin-polarized atoms to precess around the magnetic field. To comprehensively study the properties of sodium (Na) magnetometer, we present the detailed theoretical analysis of the saturated absorption spectroscopy (SAS) and the magneto-optical resonance signal in sodium D 2 line. Accordingly, we have implemented two experimental schemes, the counter propagating pump-probe SAS of thermal Na vapor and the remote sensing Bell-Bloom magnetometry based on the Larmor precession frequency. In the first experiment, sub-Doppler features of D 2 consist of two velocity selective optical pumping (VSOP) resonances located at the D 2a and D 2b transitions and a crossover (CO) resonance located between the VSOP resonances are observed. In the second experiment, an estimated intrinsic magnetometric sensitivity of δ B int = 286 pT in a 1 Hz bandwidth, is achieved by demodulating the recorded fluorescence signal of the resultant magneto-optical resonance near the 300 kHz Larmor precession frequency. Both kinds of experimental results are in good agreement with our theoretical calculations.

中文翻译：

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光泵浦钠原子的理论和实验结果

摘要 光泵浦是一个产生非热塞曼子能级分布的过程。它在碱金属磁力计中起着重要的作用，有两种用途，构建亚多普勒特征以锁定激光频率，并提供自旋极化的原子围绕磁场进动。为了全面研究钠（Na）磁强计的特性，我们对饱和吸收光谱（SAS）和钠D 2 线的磁光共振信号进行了详细的理论分析。因此，我们实施了两个实验方案，热Na蒸气的反向传播泵-探针SAS和基于Larmor进动频率的遥感Bell-Bloom磁力测定法。在第一个实验中，D 2 的亚多普勒特征包括位于 D 2a 和 D 2b 跃迁处的两个速度选择性光泵浦 (VSOP) 共振和位于 VSOP 共振之间的交叉 (CO) 共振。在第二个实验中，通过在 300 kHz 拉莫尔进动频率附近解调所得磁光共振的记录荧光信号，估计 δ B int = 286 pT 在 1 Hz 带宽内的固有磁力灵敏度。两种实验结果都与我们的理论计算非常吻合。通过解调在 300 kHz 拉莫尔进动频率附近产生的磁光共振的记录荧光信号来实现。两种实验结果都与我们的理论计算非常吻合。通过解调在 300 kHz 拉莫尔进动频率附近产生的磁光共振的记录荧光信号来实现。两种实验结果都与我们的理论计算非常吻合。