Bao Guzhi, Wickenbrock Arne, Rochester Simon, Zhang Weiping, Budker Dmitry
Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany.
Department of Physics, East China Normal University, Shanghai 200062, China.
Phys Rev Lett. 2018 Jan 19;120(3):033202. doi: 10.1103/PhysRevLett.120.033202.
The nonlinear Zeeman effect can induce splitting and asymmetries of magnetic-resonance lines in the geophysical magnetic-field range. This is a major source of "heading error" for scalar atomic magnetometers. We demonstrate a method to suppress the nonlinear Zeeman effect and heading error based on spin locking. In an all-optical synchronously pumped magnetometer with separate pump and probe beams, we apply a radio-frequency field which is in phase with the precessing magnetization. This results in the collapse of the multicomponent asymmetric magnetic-resonance line with ∼100 Hz width in the Earth-field range into a single peak with a width of 22 Hz, whose position is largely independent of the orientation of the sensor within a range of orientation angles. The technique is expected to be broadly applicable in practical magnetometry, potentially boosting the sensitivity and accuracy of Earth-surveying magnetometers by increasing the magnetic-resonance amplitude, decreasing its width, and removing the important and limiting heading-error systematic.
非线性塞曼效应可在地球物理磁场范围内引起磁共振线的分裂和不对称。这是标量原子磁力仪“航向误差”的主要来源。我们展示了一种基于自旋锁定来抑制非线性塞曼效应和航向误差的方法。在具有独立泵浦光束和探测光束的全光同步泵浦磁力仪中，我们施加一个与进动磁化同相的射频场。这导致在地磁场范围内宽度约为100 Hz的多分量不对称磁共振线坍缩为一个宽度为22 Hz的单峰，其位置在一定取向角范围内很大程度上与传感器的取向无关。预计该技术在实际磁测量中具有广泛的适用性，有可能通过增加磁共振幅度、减小其宽度以及消除重要且限制性能的航向误差系统误差来提高地勘磁力仪的灵敏度和精度。
