磁场的传感测量在相关领域具有重要应用。利用磁流体的磁光效应, 提出了一种基于光学Tamm态的磁场传感结构。该结构由加载了金属层和电介质层的一维磁流体光子晶体构成。数值研究了该结构的结构参数对传感性能的影响。结果表明, 磁流体层越厚, 探测灵敏度就越高。金属层和电介质层的厚度均存在一个最佳值, 使得传感器具有较高的探测精度。结果还表明, 该传感结构的探测灵敏度优于已报道的采用光子晶体缺陷结构实现的磁场传感器。研究结果为基于光学Tamm态的磁流体磁场传感器的设计制备提供了参考。

A compact fiber-optic magnetic field sensor is proposed by packaging an orthogonal dual-frequency fiber grating laser and a copper wire with alternating electrical current together inside epoxy resin. The alternating current generates Ampere force in a magnetic field, which changes the birefringence of the fiber laser and hence tunes the frequency of the beat signal after photodetection. The magnetic flux density can then be detected by measuring the frequency change of the beat signal. The sensitivity of the sensor can be tuned with a maximum response of 35.21 kHz/kGs demonstrated. Moreover, the sensor shows good immunity to environment interference.

基于法拉第效应，正交双频光纤激光器已经被证明可用于实现磁场传感。但这种传感器对磁场的灵敏度与激光器初始的拍频频率相关。因此对这种传感器的磁场灵敏度与拍频频率的关系进行了研究。理论和实验结果表明，传感器对磁场的灵敏度与拍频频率间呈非线性关系，并且灵敏度随着拍频频率的减小而增大。该灵敏度存在一个由费尔德常数决定的上限值。对于实验中基于掺铒光纤制备的短腔光纤激光器，通过将初始拍频频率降至2 MHz，获得了激光器对磁场响应的最大灵敏度43 Hz/μT。此外，激光器初始拍频频率与抽运激光的偏振态也有关系。实验表明，通过调谐抽运激光的偏振态，可以动态地调谐传感器对磁场的灵敏度。

利用法拉第效应,正交双偏振光纤激光器已被证明可用来实现灵活小巧的磁场传感器。 为了发展适宜的封装结构以优化对磁场的传感灵敏度,有必要研究双偏振光纤激光磁场传感器在磁场中的空间响应特性。 对长度为21 mm的光纤激光器在磁场宽度为3 mm、5 mm、7 mm以及磁场强度为0.5 T、0.75 T和1 T时的 纵向空间响应进行了实验研究。研究表明,沿着双偏振光纤激光磁场传感器的纵向,其各个部分对 磁场的空间响应是不均匀的。空间响应的峰值出现在激光腔的中间并沿激光器纵向呈对称的高斯分布。 这种空间响应的分布特性与光纤光栅的分布式布拉格反射有关。

This article describes in detail a technique for modeling cavity optomechanical field sensors. A magnetic or electric field induces a spatially varying stress across the sensor, which then induces a force on mechanical eigenmodes of the system. The force on each oscillator can then be determined from an overlap integral between magnetostrictive stress and the corresponding eigenmode, with the optomechanical coupling strength determining the ultimate resolution with which this force can be detected. Furthermore, an optomechanical magnetic field sensor is compared to other magnetic field sensors in terms of sensitivity and potential for miniaturization. It is shown that an optomechanical sensor can potentially outperform state-of-the-art magnetometers of similar size, in particular other sensors based on a magnetostrictive mechanism.