Open AccessFemtosecond-induced spiral micro-structured SMS fiber structure for refractive index measurement
Author(s) -
F Liu,
Hongfeng Lin,
Y Liu,
Ai Zhou,
Yutang Dai
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.017388
Subject(s) - femtosecond , optics , materials science , refractive index , multi mode optical fiber , spiral (railway) , optical fiber , single mode optical fiber , photonic crystal fiber , laser , optoelectronics , physics , mathematical analysis , mathematics
A single-multi-single mode (SMS) fiber structure with spiral microgroove, fabricated by femtosecond laser inscription has been proposed and successfully employed for refractive index (RI) sensing. The multimode interference in the SMS structure is effectively affected by the external perturbation due to the microgroove, which goes deep into the core of the multimode fiber (MMF). Experimental results show that this femtosecond-induced spiral micro-structured SMS (FISM-SMS) fiber structure exhibits a linear response to eternal liquid refractive index in a large RI range of 1.3373-1.4345. The maximum sensitivity of the structure can reach to 2144 nm/RIU and can be further improved by increasing the depth of the spiral micro-grooves.