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

Volume

27

Issue

23

fYear

2015

Firstpage

2461

Lastpage

2464

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 μT_rms/√Hz for an alternating magnetic field of 4.17 mT_rms.

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;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2015.2470135

Filename

7214230