大学物理 ›› 2025, Vol. 44 ›› Issue (9): 111-.

• 大学生园地 • 上一篇    

基于法拉第效应的微弱磁场测量实验设计

关欣洲,颜子顺,章心禾,罗云荣   

  1. 湖南师范大学 物理与电子科学学院,湖南长沙410081
  • 出版日期:2025-11-11 发布日期:2025-11-19

The experimental design for the measurement of weak magnetic fields based on Faraday principle

GUAN Xinzhou, YAN Zishun, ZHANG Xinhe, LUO Yunrong    

  1. School of Physics and Electronics, Hunan Normal University, Changsha 410081, Hunan
  • Online:2025-11-11 Published:2025-11-19

摘要: 本文基于法拉第效应及其非互易性原理,构建了一套能够全方位测量均匀与非均匀微弱磁场的实验装置. 该装置选用具有非互易性特征的 ZF6 重火石玻璃作为磁光介质,通过巧妙地设计光路使激光束多次经过该磁光介质,从而有效放大磁致旋光角的变化幅度. 利用光电二极管与I/V转换放大器,将磁致旋光角的变化转换为电压信号的变化,仅通过电压表或Arduino开发板采集电压数据,即可得到磁场强度. 实验结果表明,该装置测量精度高、响应快、成本低、操作简便.


关键词: 微弱磁场测量, 法拉第效应, 磁光介质, 光电检测

Abstract: This article describes the construction of an experimental apparatus based on the Faraday effect and its non-reciprocal principle for omnidirectional detection of weak uniform and non-uniform magnetic fields. The system employs ZF6 heavy flint glass, a magneto-optical medium with intrinsic non-reciprocal properties. By implementing a multi-pass optical configuration to propagate the laser beam through the medium repeatedly, the magnetically induced rotation angle variations are amplified. Photodiodes integrated with transimpedance amplifiers convert these angular variations into quantifiable voltage signal modulations, magnetic field strength is obtained solely through voltage data acquisition utilizing either a voltmeter or an Arduino development board. Experimental results confirm that the device achieves high measurement accuracy, rapid response characteristics, low-cost implementation, and user-friendly operation.

Key words: weak magnetic field measurement, the Faraday effect, magneto-optical media, Photoelectric detection