Fiber optic EFPI-based sensor for low magnetic field measurement

There has been considerable interest in developing high sensitivity fiber optic magnetic field sensors using primarily interferometric configurations In this paper, a fiber optic sensor based on the extrinsic Fabry-Perot interferometer (EFPI) is demonstrated to measure low DC-magnetic fields (100 Oe - 40,000 Oe). A Metglas (Fe/sub 77.5/B/sub 15/Si/sub 7.5/) wire-based magnetostrictive transducer is used as the reflector in the EFPI sensor. The simple sensor geometry gives both low vibration sensitivity and high temperature stabilization.