Abstract

A long period fiber grating (LPFG) sensor has been fabricated, after theoretical analysis, obtaining the maximum enhancement of the evanescent field working with the lowest order cladding mode (LP_0,2 cladding mode) near turn around point. Both the wavelengths of the dual peak resonance and the coupling conditions of the mode have been analyzed in detail. A flow cell has been fabricated to characterize the sensor in term of surrounding refractive index (SRI) sensitivity. The sensitivity of the sensor resulted to be ∼8751 nm/SRIU, with a resolution in the order of 10⁻⁵, within the SRI range of 1.333 to 1.3335.

CO₂ laser-written long-period fiber grating with a high diffractive order cladding mode near the turning point

Zuyao Liu, Yunqi Liu, Chengbo Mou, Fang Zou, and Tingyun Wang
Appl. Opt. 57(17) 4756-4760 (2018)

Smart design of a long-period fiber grating refractive index sensor based on dual-peak resonance near the phase-matching turning point

Qiang Ling, Zhengtian Gu, and Kan Gao
Appl. Opt. 57(10) 2693-2697 (2018)

Sensitivity optimization with cladding-etched long period fiber gratings at the dispersion turning point

Ignacio Del Villar, Jose L. Cruz, Abian B. Socorro, Jesus M. Corres, and Ignacio R. Matias
Opt. Express 24(16) 17680-17685 (2016)

Ultrahigh-sensitivity sensors based on thin-film coated long period gratings with reduced diameter, in transition mode and near the dispersion turning point

Ignacio Del Villar
Opt. Express 23(7) 8389-8398 (2015)

Simultaneous measurement of the surrounding refractive index and temperature using a local-micro-structured long-period fiber grating sensor operating near the phase-matching turning point

Ying Wang, Zhengyuan Li, Bo Pang, Xinyu Wang, Yihao He, Jinghong Zhang, Leaven Romeo Mupfukirei, Kai Zhang, Qiang Ling, Zhangwei Yu, and Daru Chen
J. Opt. Soc. Am. B 41(4) 915-920 (2024)