Magnetic field sensor based on magnetic fluid with side-polished fiber Bragg grating

Abstract

A novel optical fiber magnetic sensor based on magnetic fluid is proposed in this paper. Stable nano-particle CoFe₂O₄magnetic fluid was synthesized firstly; the CoFe₂O₄ magnetic fluid was injected in capillaries containing side-polished fiber Bragg grating (SPFBG) as sensing element. The reflected Bragg wavelength was changed by varying the magnetic field which is perpendicular to the axial of SPFBG. Magnetic field sensing experiment show that 35pm of wavelength shift at a magnetic field intensity of 16mT.