Based on the unique polarization characteristic of the cylindrical vector beam, a new-type vector magnetic field sensing technique is proposed. As the cylindrical vector beam passes through a magnetic fluid film, a polarization analyzer is used to detect the polarization state change of the output light after passing through a slit. Based on the birefringence effect, the direction of the magnetic field can be resolved by the direction of the maximum ellipticity, while the magnetic field strength can be obtained by the change of the maximum ellipticity. Both of the magnetic field strength and direction in the X-Y plane could be measured simultaneously. The experimental results show that the direction error is less than 2°, the strength error is less than 10 Gs, and the sensitivity of the strength of magnetic field is 0.12 °/Gs. Therefore, the proposed technique would be promising for two-dimensional magnetic field detection and safety detection, such as high-voltage discharge magnetic field detection.

中文翻译：

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基于磁流体的矢量磁场传感圆柱形矢量束


基于圆柱矢量光束独特的偏振特性，提出了一种新型矢量磁场传感技术。当柱面矢量光束穿过磁性流体膜时，使用偏振分析器来检测输出光通过狭缝后的偏振态变化。基于双折射效应，可以通过最大椭圆率的方向来解析磁场的方向，而通过最大椭圆率的变化可以得到磁场强度。可以同时测量XY平面内的磁场强度和方向。实验结果表明，方向误差小于2°，强度误差小于10 Gs，磁场强度灵敏度为0.12°/Gs。因此，所提出的技术将有望用于二维磁场检测和安全检测，例如高压放电磁场检测。