Numerical Investigation of a Highly Sensitive Plasmonic Refractive Index Sensor for the Detection of Breast and Cervical Cancer Biomarkers

In this study, we introduce an innovative plasmonic refractive index (RI) sensor that seamlessly integrates with a straight waveguide. This design has been expertly tailored to complement a metal-insulator-metal (MIM) waveguide structure, ensuring optimal performance and efficiency. We conducted an in-depth numerical analysis using the finite element method (FEM) to evaluate the sensor's performance comprehensively. The sensor is designed to detect shifts in the resonant wavelength, which correspond to changes in the refractive index (RI). Our sensor functions based on the principle that its effectiveness depends on the interaction of light with the plasmonic structure. By detecting shifts in the resonant wavelength, our sensor responds to changes in the surrounding medium's refractive index (RI), a key attribute for applications ranging from biosensing to chemical analysis. Our optimization process has led to the sensor achieving exceptional sensitivity, with a peak value of 1955 nm/RIU. This remarkable sensitivity enables the detection of trace amounts of molecules, highlighting the sensor's effectiveness in applications that require precise molecular detection. We also investigated the sensor's application in medical diagnostics through detailed numerical evaluations, focusing on its capability to detect biomarkers associated with breast and cervical cancer.