Fabrication of a Chemical Sensor Based on Surface Plasmon Resonance via Plastic Optical Fiber

Ghufran Mohammed Jassam,Soudad S. Alâ€“Bassam,Murtadha F. Sultan

doi:10.24996/ijs.2020.61.4.8

Ghufran Mohammed Jassam, Soudad S. Alâ€“Bassam + Show 1 more

Open Access

https://doi.org/10.24996/ijs.2020.61.4.8

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Abstract

In this work, a chemical optical fiber sensor based on Surface Plasmon Resonance (SPR) was designed and implemented using plastic optical fiber. The sensor is used for estimating refractive indices and concentrations of various chemical materials (methanol, distilled water, ethanol, kerosene) as well as for evaluating the performance parameters such as sensitivity, signal to noise ratio, resolution and the figure of merit of the fabricated sensor. It was found that the value of the sensitivity of the optical fiber-based SPR sensor, with 40 nm thick and 10 mm long Au metal film of exposed sensing region, was 3Î¼m/RIU, while the SNR was 0.24, the figure of merit was 20, and the resolution was 0.00066. The sort of optical fiber utilized in this work is plastic optical fiber with a core diameter of 980 Î¼m, a fluorinated polymer cladding of 20Î¼m and a numerical aperture of 0.51.

Highlights

Optical fiber sensors have wide applications in science, environmental monitoring, and communication technology
The combination of the surface Plasmon’s Resonance (SPR) technique and optical fiber technology has been intensively used for the sensing of various entities such as refractive index of the fluid, film thickness, surface roughness, pH, temperature, as well as levels of urea, glucose, pollutions and different types of gases [4, 5]
The first study on fiber optic chemical sensors that are based on SPR was reported in 1993 by Jorgenson and Yee [6]

Summary

Introduction

Optical fiber sensors have wide applications in science, environmental monitoring, and communication technology. The surface Plasmon’s Resonance (SPR) is one of the promising optical techniques that indicate the stimulation of surface Plasmon’s , due to the high sensitivity to changes in the refractive index in the surrounding medium. This technique has a broad spectrum of applications in biology, environment, chemistry, medicine, etc.[3]. SPR is a high-sensitivity optical sensing method that was utilized for the real-time detection of little variations in the active refractive index of dielectric-metal interfaces This method was dependent on the interaction between free electrons of the metallic layer and light. Figure- 5 demonstrates the linear relationship between the refractive index and the solution concentration

Results and Discussion

Conclusions