Ag-Au Alloy-Based Highly-Sensitive Plasmonic Sensor
Date
2025-10-25
Journal Title
Journal ISSN
Volume Title
Publisher
Department of Electrical and Electronic Engineering (EEE), Islamic University of Technology(IUT), Board Bazar, Gazipur-1704, Bangladesh
Abstract
The proposed refractive index sensor has an alloy-insulator-alloy construction. Au-Ag
alloy provides several advantages over pure metal in terms of chemical stability, per
formance and fabricability. The material under the sensing unit features interdigitated
finger-like structures with a metallic nanorod inserted into it. When air is used as an
insulator in conjunction with an alloy, our sensor has demonstrated better performance
than with pure metal. It has attained a sensitivity of 3730 nm/RIU and FOM of 9.29
for 50%-50% Au-Ag concentration. Later, we have used Ta205 as the dielectric medium
since it has a higher bandgap and a high refractive index, paving the way for stronger
mode confinement. That’s why we have replaced the air medium with Ta205 in our final
structure. Eventually, with a suitable metallic alloy composition, our sensor exhibits a
maximum sensitivity and FOM of 4750 nm/RIU and 29.83, respectively. Furthermore,
the wide operating region of the RI sensor helps to encompass multiple applications.
We have utilized our proposed structure to efficiently measure blood concentration. It
can also specifically determine hemoglobin concentration with minimal error percent
age. Besides that, edible oil can easily be classified based on the resonant wavelength
shift. Overall, the unique sensor structure, when employed with alternative materials,
demonstrates exceptional performance and versatile applicability
Description
Supervised by
Prof. Dr. Rakibul Hasan Sagor,
Department of Electrical and Electronic Engineering (EEE)
Islamic University of Technology (IUT)
Board Bazar, Gazipur, Bangladesh
This thesis is submitted in partial fulfillment of the requirement for the degree of Bachelor of Science in Electrical and Electronic Engineering, 2025
Keywords
Citation
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