Schultze Volkmar, Scholtes Theo, Oelsner Gregor, Wittkaemper Florian, Wieduwilt Torsten, Stolz Ronny
Leibniz Institute of Photonic Technology Jena, Albert-Einstein-Straße 9, D-07745 Jena, Germany.
Sensors (Basel). 2023 Aug 2;23(15):6866. doi: 10.3390/s23156866.
In mobile applications such as geomagnetic surveying, two major effects hamper the use of optically pumped magnetometers: dead zones, sensor orientations where the sensors signal amplitude drops; and heading errors, a dependence of the measured magnetic field value on the sensor orientation. We present a concept for an omnidirectional magnetometer to overcome both of these effects. The sensor uses two cesium vapor cells, interrogated by circularly-polarized amplitude-modulated laser light split into two beams propagating perpendicular to each other. This configuration is experimentally investigated using a setup wherein the laser beam and magnetic field direction can be freely adjusted relative to each other within a magnetically shielded environment. We demonstrate that a dead-zone-free magnetometer can be realized with nearly isotropic magnetic-field sensitivity. While in the current configuration we observe heading errors emerging from light shifts and shifts due to the nonlinear Zeeman effect, we introduce a straightforward approach to suppress these systematic effects in an advanced sensor realization.
在诸如地磁测量等移动应用中，有两种主要效应阻碍了光泵磁力仪的使用：死区，即传感器信号幅度下降的传感器取向；以及航向误差，即测量的磁场值对传感器取向的依赖性。我们提出了一种全向磁力仪的概念，以克服这两种效应。该传感器使用两个铯蒸汽室，由圆偏振振幅调制激光束照射，该激光束被分成两束相互垂直传播的光束。使用一种装置对这种配置进行了实验研究，在该装置中，激光束和磁场方向可以在磁屏蔽环境中相对于彼此自由调整。我们证明，可以实现具有几乎各向同性磁场灵敏度的无死区磁力仪。虽然在当前配置中，我们观察到由于光频移和非线性塞曼效应引起的航向误差，但我们引入了一种直接的方法来在先进的传感器实现中抑制这些系统效应。
