Simultaneous detection of SRI and temperature with a FM-LPFG sensor based on dual-peak resonance

• DOI: 10.1364/josab.36.002210
• Publication Date: 2019-07-22T15:54:57Z
• Authors: Qiang Ling; Zhengtian Gu
• Keywords: Cladding (metalworking); Long-period fiber grating

A novel few-mode long-period fiber grating (FM-LPFG) sensor based on dual-peak resonance near the phase-match turning point (PMTP) for simultaneous detection of surrounding refractive index (SRI) and temperature is proposed. The PMTP FM-LPFG analyzed coupled-mode theory. cladding modes adjacent order exhibit single-peak resonances in wavelength band 1450–1850 nm, respectively. And response characteristics different resonant peaks to SRI are discussed. Results numerical simulations demonstrate that sensitivities corresponding distance between dual transmissivity 1114.28 nm/RIU -685.42 dB/RIU, respectively, −0.27 nm/°C 0.072 dB/°C. those help sense multi-parameters.