Title :
Intensity-Modulated Optical Fiber Sensor for AC Magnetic Field Detection
Author :
Nascimento, Ivo M. ; Baptista, J.M. ; Jorge, P.A.S. ; Cruz, Jose L. ; Andres, Miguel V.
Author_Institution :
Inst. de Eng. de Sist. e Comput., Tecnol. e Cienc., Porto, Portugal
Abstract :
An erbium-doped (Er3+) fiber optic laser is proposed for sensing alternated magnetic fields by measuring the laser intensity modulation. The sensor is fabricated using two partially overlapped narrow-band fiber Bragg gratings (FBGs) and a section of doped fiber in a Fabry-Perot configuration. Laser power stability and bandwidth are studied while changing the overlap. A bulk rod of TbDyFe, a magnetostrictive material, is glued to both the FBGs and the laser wavelength and power are modulated according to the magnetic field. Acquisition and processing are done using virtual instrumentation. Results have shown the possibility of detecting 11.18 μTrms/√Hz for an alternating magnetic field of 4.17 mTrms.
Keywords :
Bragg gratings; erbium; fibre lasers; fibre optic sensors; intensity modulation; magnetic sensors; magneto-optical devices; magnetoresistance; optical modulation; terbium compounds; AC magnetic field detection; FBG; Fabry-Perot configuration; TbDyFe; alternated magnetic field; erbium-doped fiber optic laser; intensity-modulated optical fiber sensor; laser bandwidth; laser intensity modulation; laser power stability; laser wavelength; magnetostrictive material; partially overlapped narrow-band fiber Bragg gratings; virtual instrumentation; Fiber gratings; Magnetic field measurement; Magnetic fields; Magnetostriction; Optical fiber sensors; Optical fibers; Magnetic field sensor; erbium doped fiber laser; intensity modulation; magnetic field sensor; magnetostrictive material;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2015.2470135
