1. A Highly Sensitive Intensity-Modulated Optical Fiber Magnetic Field Sensor Based on the Magnetic Fluid and Multimode Interference
- Author
-
Xuekun Bai, Weilong Dong, Fufei Pang, Chuanlu Deng, Tingyun Wang, Liangjiang Wang, Zhang Xiaobei, Zhenyi Chen, and Yi Huang
- Subjects
Materials science ,Optical fiber ,Article Subject ,Physics::Optics ,Polarization-maintaining optical fiber ,02 engineering and technology ,01 natural sciences ,Graded-index fiber ,law.invention ,010309 optics ,Mode field diameter ,Optics ,law ,0103 physical sciences ,lcsh:Technology (General) ,Dispersion-shifted fiber ,Electrical and Electronic Engineering ,Instrumentation ,Multi-mode optical fiber ,business.industry ,021001 nanoscience & nanotechnology ,Control and Systems Engineering ,Fiber optic sensor ,lcsh:T1-995 ,0210 nano-technology ,business ,Intensity modulation - Abstract
Fiber-optic magnetic field sensing is an important method of magnetic field monitoring, which is essential for the safety of civil infrastructures, especially for power plant. We theoretically and experimentally demonstrated an optical fiber magnetic field sensor based on a single-mode-multimode-single-mode (SMS) structure immersed into the magnetic fluid (MF). The length of multimode section fiber is determined based on the self-image effect through the simulation. Due to variation characteristics of the refractive index and absorption coefficient of MF under different magnetic fields, an effective method to improve the sensitivity of SMS fiber structure is realized based on the intensity modulation method. This sensor shows a high sensitivity up to 0.097 dB/Oe and a high modulation depth up to 78% in a relatively linear range, for the no-core fiber (NCF) with the diameter of 125 μm and length of 59.8 mm as the multimode section. This optical fiber sensor possesses advantages of low cost, ease of fabrication, high sensitivity, simple structure, and compact size, with great potential applications in measuring the magnetic field.
- Published
- 2017