Refractive index sensor performance based on enhanced transmission of light through perforated metallic films

In this paper, we propose and numerically analyze a novel design for a high sensitivity refractive index (RI) sensor based on long-range surface plasmon resonance in H-shaped microstructured optical fiber with symmetrical dielectric–metal–dielectric waveguide (DMDW). The influences of geometrical and optical characteristics of the DMDW on the sensor performance are investigated theoretically. A large RI analyte range from 1.33 to 1.39 is evaluated to study the sensing characteristics of the proposed structure. The obtained results show that the DMDW improves the coupling between the fiber core mode and the plasmonic mode. The best configuration shows 27 nm of full width at half maximum with a resolution close to 1.3 × 10 − 5 nm, a high sensitivity of 7540 nm/RIU and a figure of merit of 280 RIU − 1 . Additionally, the proposed device has potential for multi-analyte sensing and self-reference when dissimilar DMDWs are deposited on the inner walls of the side holes. The proposed sensor structure is simple and presents very competitive sensing parameters, which demonstrates that this device is a promising alternative and could be used in a wide range of application areas.

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Plasmonic Refractive Index Sensor Based on Resonant System with Two Plasmonic Waveguides, Two Rings and Two Cavities

10.20944/preprints202110.0141.v1 ◽

2021 ◽

Author(s):

Hamid Abbasi

Keyword(s):

Refractive Index ◽

Quality Factor ◽

Field Distribution ◽

Surface Plasmon ◽

Sensitivity Coefficient ◽

Refractive Index Sensor ◽

Plasmonic Waveguides ◽

Resonant System ◽

Sensor Performance ◽

Five Factors

In this research, we seek to design and numerically evaluate a refractive index sensor based on the resonant system with metal insulating waveguide (MIM) that includes a wide range of wavelengths. To design the structure of this sensor, we use two rings with different dimensions and two cavities and two plasmonic waveguides. The resonant wavelengths and the refractive index of the resonators have been studied and simulated by the finite difference time domain (FDTD) method, which directly obtains the Maxwell equations by proper separation in the two time and space domains (But all the diagrams in this article are obtained using MATLAB). We send an electromagnetic wave to the structure of the sensor we have designed to analyze the field distributions and the spectral response of the structural parameters. When the field distribution is in the same structure, the energy loss is reduced. To achieve the maximum field distribution in the structure, all dimensions must be optimal. Intensification of the surface plasmon at the boundary between a metal surface and the dielectric material (sensor structure and waveguides) will increase the electric field strength and correct the sensor performance. Nanoparticle surface plasmon resonance depends on five factors: size, shape, nanoparticle composition, particle distance, and refractive index of the nanoparticle environment. These five factors affect the wavelength and intensity of the peak. To measure sensor performance, it calculates factors such as resolution, transmission efficiency, adjustable range of wavelengths, S sensitivity coefficient, FOM, Q quality factor and quality factor and width factor at half maximum value (FWHM). To achieve a functional plasmonic sensor. This sensor is suitable for use in fully integrated circuits as well as for the detection of chemical, biological and biological materials due to its high resolution accuracy, low size, high FOM value and high sensitivity coefficient.

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