Tang Junjian, Yin Yan, Zhai YueYang, Zhou Binquan, Han Bangcheng, Yang Hongying, Liu Gang
Opt Express. 2021 Mar 15;29(6):8333-8343. doi: 10.1364/OE.418776.
In this paper, we experimentally study transient dynamics of spin polarized atoms in the spin-exchange-relaxation-free (SERF) regime with a single-beam configuration. We pumped atoms with a weak detuning pumping beam, along with a sequence of magnetic field pulses orthogonal to the pumping beam were applied. The dynamics of atomic spin, which experiences Larmor precession under the perturbation of magnetic field, is detected by the transmitted pumping beam. Benefited from the long coherence time of atomic spin in the SERF regime, the dependence of precession frequency and decay rate, which is equal to the magnetic resonance linewidth of atomic spin, on magnetic fields is studied with the transient dynamics of atomic spin in the limit of low spin polarization. Moreover, we demonstrate that coil constants can be calibrated by analyzing the precession frequency of the transient dynamics of atomic spin. And the experimental results show that the coil constants are 114.25 ± 0.02 nT/mA and 114.12 ± 0.04 nT/mA in x- and y-axis, respectively. This method is particularly applicable to study the atomic spin dynamics and calibrate the coil constant in situ of a miniature single-beam SERF magnetometer.
在本文中，我们通过单光束配置对自旋交换无弛豫（SERF） regime下的自旋极化原子的瞬态动力学进行了实验研究。我们用弱失谐泵浦光束泵浦原子，并施加一系列与泵浦光束正交的磁场脉冲。原子自旋在磁场扰动下经历拉莫尔进动，其动力学通过透射泵浦光束进行检测。受益于SERF regime下原子自旋的长相干时间，在低自旋极化极限下，利用原子自旋的瞬态动力学研究了进动频率和衰减率（等于原子自旋的磁共振线宽）对磁场的依赖性。此外，我们证明了可以通过分析原子自旋瞬态动力学的进动频率来校准线圈常数。实验结果表明，x轴和y轴的线圈常数分别为114.25±0.02 nT/mA和114.12±0.04 nT/mA。该方法特别适用于研究微型单光束SERF磁力计中原子自旋动力学并原位校准线圈常数。
