The principles and performance of a fiber-optic Faraday-effect magnetic-field sensor designed around an yttrium-iron-garnet (YIG) sensing element and two flux concentrators are described. The system design exploits the technique of polarization-rotated reflection in which a single polarization-maintaining optical fiber links the sensor head to the optical source and detection system. In the sensing head, ferrite flux concentrators are magnetically coupled to the YIG sensing element to achieve maximum sensitivity. The system exhibits a noise equivalent field of 6 pT/√Hz and a 3-dB bandwidth of ∼ 10 MHz.
© 1996 Optical Society of America
Original Manuscript: March 21, 1995
Revised Manuscript: August 29, 1995
Published: January 1, 1996
Merritt N. Deeter, "Fiber-optic Faraday-effect magnetic-field sensor based on flux concentrators," Appl. Opt. 35, 154-157 (1996)