High Sensitivity Refractive Index Sensor Based on a Tapered Small Core Single-Mode Fiber Structure.

Authors

Dejun Liu, Technological University DublinFollow
Arun Mallik, Technological University DublinFollow
Jinhui Yuan, Department of Physics and Electrical Engineering, Northumbria University, UK
Chongxiu Yu, Beijing University of Posts and Telecommunication, Beijing, China,
Gerald Farrell, Technological University DublinFollow
Yuliya Semenova, Technological University DublinFollow
Qiang wu, Technological University DublinFollow

Document Type

Article

Rights

Available under a Creative Commons Attribution Non-Commercial Share Alike 4.0 International Licence

Disciplines

2. ENGINEERING AND TECHNOLOGY

Publication Details

Optics Letters.

Abstract

A high sensitivity refractive index (RI) sensor based on a tapered small core single-mode fiber (SCSMF) structure sandwiched between two traditional single-mode fibers (SMF28) is reported. The microheater brushing technique was employed to fabricate the tapered fiber structures with different waist diameters of 12.5, 15.0, and 18.8 μm. Experiments demonstrate that the fiber sensor with a waist diameter of 12.5 μm offers the best sensitivity of 19212.5  nm/RIU19212.5  nm/RIU (RI unit) in the RI range of 1.4304 to 1.4320. All sensors fabricated in this Letter show good linearity in terms of the spectral wavelength shift versus changes in RI. Furthermore, the sensor with the best sensitivity to RI was also used to measure relative humidity (RH) without any coating materials applied to the fiber surface. Experimental results show that the spectral wavelength shift changes exponentially as the RH varies from 60% to 95%. A maximum sensitivity of 18.3 nm per relative humidity unit (RHU) was achieved in the RH range of 90.4% to 94.5% RH.

Recommended Citation

Mallik, A. (2015). High sensitivity refractive index sensor based on a tepered small core single-mode fiber structure. Optics Letters, vol. 40, no. 17, pp. 4166-4169. doi:10.1364/OL.40.004166.