High sensitive LPFG magnetic field sensor based on dual-peak resonance

Fiber optic magnetic field sensor using Co doped ZnO nanorods as cladding

“…Hitherto, various kinds of fiber optic based magnetic sensor have been proposed using magnetic fluid (MF) as the cladding with different optical devices such as Fiber Bragg Grating (FBG), 22 Long Period Fiber Bragg Grating (LPFG), 23 single-mode–multi-mode–single-mode (SMS) structures, 24 multi-mode–single-mode–multi-mode (MSM) structures, 25 micro resonators, 26 and Fabry–Pérot devices. 27 However, minor shortcomings like the feeble response of MF to external magnetic fields, low interaction between core mode/lower order cladding mode and MF, structure instability and complicated technology mean that they fail to achieve higher magnetic sensitivity.…”

Design of a coated thinly clad chalcogenide long-period fiber grating refractive index sensor based on dual-peak resonance near the phase matching turning point

“…[6,7] When the actual grating period is less than the corresponding period of the PMTP, the LPFG has two resonance peaks that exhibit a dual-peak resonance effect. [8][9][10] At the same time, if the temperature, [11] ambient refractive index [12] and strain [13] change slightly, the bimodal resonant wavelength will change accordingly. Chen and Gu observed that a LPFG sensor based on bimodal resonance worked near the PMTP and had a high sensitivity to the SRI.…”