High Sensitivity Refractometer Based on Reflective Smf-Small Diameter No Core Fiber Structure

Guorui Zhou; Qiang Wu; Rahul Kumar; Wai Pang Ng; Hao Liu; Longfei Niu; Nageswara Lalam; Xiaodong Yuan; Yuliya Semenova; Gerald Farrell; Jinhui Yuan; Chongxiu Yu; Jie Zeng; Gui Yun Tian; Yong Qing Fu

doi:10.3390/s17061415

High Sensitivity Refractometer Based on Reflective Smf-Small Diameter No Core Fiber Structure

Sensors (Basel). 2017 Jun 16;17(6):1415. doi: 10.3390/s17061415.

Authors

Guorui Zhou^{1

2}, Qiang Wu³, Rahul Kumar⁴, Wai Pang Ng⁵, Hao Liu⁶, Longfei Niu⁷, Nageswara Lalam⁸, Xiaodong Yuan⁹, Yuliya Semenova¹⁰, Gerald Farrell¹¹, Jinhui Yuan¹², Chongxiu Yu¹³, Jie Zeng¹⁴, Gui Yun Tian¹⁵, Yong Qing Fu¹⁶

Affiliations

¹ Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China. zhougr@caep.cn.
² Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK. zhougr@caep.cn.
³ Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK. qiang.wu@northumbira.ac.uk.
⁴ Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK. lh_liuhao_1989@126.com.
⁵ Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK. niulf12@lzu.edu.cn.
⁶ Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China. xdyuan@caep.cn.
⁷ Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China. rahul.kumar@northumbria.ac.uk.
⁸ Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK. wai-pang.ng@northumbria.ac.uk.
⁹ Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China. nageswara.lalam@northumbria.ac.uk.
¹⁰ Photonics Research Centre, Dublin Institute of Technology, Dublin 8, Ireland. richard.fu@northumbria.ac.uk.
¹¹ Photonics Research Centre, Dublin Institute of Technology, Dublin 8, Ireland. yuliya.semenova@dit.ie.
¹² State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China. gerald.farrell@dit.ie.
¹³ State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China. yuanjinhui81@bupt.edu.cn.
¹⁴ State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. cxyu@bupt.edu.cn.
¹⁵ School of Electrical, Electronic and Computer Engineering, Newcastle University, Newcastle Upon Tyne NE1 7RU, UK. Jie.Zeng@newcastle.ac.uk.
¹⁶ Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK. g.y.tian@newcastle.ac.uk.

Abstract

A high sensitivity refractive index sensor based on a single mode-small diameter no core fiber structure is proposed. In this structure, a small diameter no core fiber (SDNCF) used as a sensor probe, was fusion spliced to the end face of a traditional single mode fiber (SMF) and the end face of the SDNCF was coated with a thin film of gold to provide reflective light. The influence of SDNCF diameter and length on the refractive index sensitivity of the sensor has been investigated by both simulations and experiments, where results show that the diameter of SDNCF has significant influence. However, SDNCF length has limited influence on the sensitivity. Experimental results show that a sensitivity of 327 nm/RIU (refractive index unit) has been achieved for refractive indices ranging from 1.33 to 1.38, which agrees well with the simulated results with a sensitivity of 349.5 nm/RIU at refractive indices ranging from 1.33 to 1.38.

Keywords: no core fiber; optical fiber sensor; refractometer; single mode-multimode-single mode (SMS) structure.