Simultaneous measurement of both magnetic field strength and temperature with a microfiber coupler based fiber laser sensor

Abstract

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Multiparameter fiber-optic sensors: a review

“…An example of combined temperature-magnetic field sensor (utilizing magneto-optic liquid that changes RI as a function of the B-field) was described in Ref. 165. In a similar way, simultaneous measurement of temperature and strain was also reported in Ref.…”

Temperature-compensated magnetic field sensing with a dual-ring structure consisting of microfiber coupler-Sagnac loop and fiber Bragg grating-assisted resonant cavity

“…A variety of fiber-optic structures have been proposed for magnetic field sensing. Optical microfiber couplers (MFCs) have become a topic of special interest in optical fiber sensing due to their excellent sensing properties [5,6]. Microfiber-based magnetic field sensors show higher sensitivity to surrounding refractive index (RI) than traditional optical structures utilizing interference, because their much smaller diameter means that a larger proportion of the evanescent field surrounding the microfiber can interact with the local environment.…”

“…However, this sensor was difficult to fabricate with precision. Previously we proposed a similar dual-ring structure consisting of an MFC-Sagnac loop and an FBG-assisted resonant cavity [5]. However, the sensitivity was only 15 pm/mT in the magnetic field range from 0 to 100 mT and 13 pm/°C in the temperature range from 25°C to 44°C.…”