title: Fiber refractometer based on a fiber Bragg grating and single-mode-multimode-single-mode fiber structure.
abstract: A refractive index (RI) sensor based on a novel fiber structure that consists of a single-mode-multimode-single-mode (SMS) fiber structure followed by a fiber Bragg grating was demonstrated. The multimode fiber in the SMS structure excites cladding modes within output single-mode fiber (SMF) and recouple the reflected cladding Bragg wavelength to the input SMF core. By measuring the relative Bragg wavelength shift between core and cladding Bragg wavelengths, the RI can be determined. Experimentally we have achieved a maximum sensitivity of 7.33 nm/RIU (RI unit) at RI range from 1.324 to 1.439.
authors.affiliation: Photonics Research Center, School of Electronic and Communications Engineering, Dublin Institute of Technology, Kevin Street, Dublin 8, Ireland. qiang.wu@dit.ie
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wu
authors.forename: Yuliya
authors.initials: Y
authors.lastname: Semenova
authors.forename: Binbin
authors.initials: B
authors.lastname: Yan
authors.forename: Youqiao
authors.initials: Y
authors.lastname: Ma
authors.forename: Pengfei
authors.initials: P
authors.lastname: Wang
authors.forename: Chongxiu
authors.initials: C
authors.lastname: Yu
authors.forename: Gerald
authors.initials: G
authors.lastname: Farrell