Enhanced Alcohol Detection Using Surface Plasmon Polariton Dependent MIM Plasmonic Sensor

In our research, we present a groundbreaking L-shaped plasmonic refractive index (RI) sensor, coupled with a straight metal-insulator-metal (MIM) waveguide configuration. Employing the finite element method (FEM), we conduct a meticulous numerical analysis to delve into the intricacies of our proposed structure. This sensor primarily aims to detect alterations in RI by tracking changes in the resonant wavelength. The sensing principle hinges on the interaction between light and the plasmonic structure, where variations in the RI of the surrounding medium induce shifts in the resonant wavelength. Such a mechanism holds immense significance, particularly in the realm of chemical analysis. To enhance the sensor’s efficacy, we embark on a rigorous process of geometric parameter optimization. Our efforts yield promising results, with the sensor exhibiting a remarkable maximum sensitivity of 1638 nm/RIU. This exceptional capability allows for the discernment of minuscule quantities of molecules, thereby establishing its superiority in molecular detection applications. Moreover, we extend the utility of our proposed sensor by conducting numerical analyses to evaluate its performance in detecting various types of alcohol.