Xiong Ziyang, Guan Chunying, Duan Zhenyu, Cheng Tailei, Ye Peng, Yang Jing, Shi Jinhui, Yang Jun, Yuan Libo, Grattan K T V
Opt Express. 2022 Jun 20;30(13):22746-22754. doi: 10.1364/OE.460692.
A magnetic field sensor based on a side-polished two-core fiber (SPTCF)-based Michelson interferometer (MI) has been developed and demonstrated. The magnetic field sensor is composed of a standard single mode fiber (SMF) and a section of tapered TCF. By side-polishing a segment of the TCF, the effective index of the exposed core can be made sensitive to the environmental refractive index (RI). To evaluate its performance, a magnetic fluid is used to cover the polished region with a magnetic field sensitive material, where the sensor then measures the magnetic field intensity by sensing the RI change of the magnetic fluid through the evanescent field in the polished core. The SPTCF MI device developed allows for vector magnetic field sensing because of its asymmetric structure, with its highest directional sensitivity being 55.2 pm/degree. Experimental results obtained show that when the magnetic field is parallel to the side-polished plane, a sensitivity of 1.262 nm/mT can be achieved, operating over the magnetic flux density region of 0-5 mT and over a temperature range of 20∼85 °C, where the device is minimally affected by temperature changes. The sensor is well suited to a variety of potential applications given its low cost, strong anti-interference ability, simple structure and high stability.
一种基于侧面抛磨双芯光纤（SPTCF）的迈克尔逊干涉仪（MI）的磁场传感器已被研制并展示。该磁场传感器由一根标准单模光纤（SMF）和一段锥形双芯光纤（TCF）组成。通过对一段TCF进行侧面抛磨，可使暴露纤芯的有效折射率对环境折射率（RI）敏感。为评估其性能，使用一种磁性流体覆盖抛磨区域，该区域含有磁场敏感材料，传感器通过倏逝场感应磁性流体的折射率变化来测量磁场强度。所研制的SPTCF MI装置因其不对称结构可实现矢量磁场传感，其最高方向灵敏度为55.2皮米/度。获得的实验结果表明，当磁场平行于侧面抛磨平面时，在0 - 5毫特斯拉的磁通密度区域以及20至85摄氏度的温度范围内，可实现1.262纳米/毫特斯拉的灵敏度，且该装置受温度变化影响最小。鉴于其成本低、抗干扰能力强、结构简单且稳定性高，该传感器非常适合各种潜在应用。
