کنفرانس بین المللی میکروالکترونیک ایران

صفحه اصلی / هفتمین کنفرانس بین المللی میکروالکترونیک ایران

A Compact Biomedical MIM Plasmonic Refractive Index Sensor with Structurally Defective Nano-Islands for Electrolyte Detection

نویسندگان :

Mohammad Ghanavati¹ Mardin Rostampour² Mohammad Azim Karami³

1- Iran university of science and technology 2- Iran university of science and technology 3- Iran university of science and technology

کلمات کلیدی :

Plasmonic sensor،MIM waveguide،High-resolution detection،Structural defects،Finite Element Method (FEM)،Sodium and potassium detection

چکیده :

We present a compact plasmonic sensor for refractive index detection utilizing a metal-insulator-metal (MIM) waveguide integrated with a disk-shaped cavity containing three structurally defective silver nano-islands. The islands are incomplete (non-fully closed) disks, symmetrically placed at the vertices of an equilateral triangular configuration within the main disk cavity. Two configurations with and without geometric defects are analyzed by employing the finite element method (FEM). The defective nano-islands exhibit improved optical performance, including higher transmission, narrower full width at half maximum (FWHM), and an enhanced quality factor (QF = 119.7). The optimized sensor demonstrates high refractive index sensitivity (~1028.6 nm/RIU) and a detection resolution of ~1.3 × 10-⁶ RIU. Additionally, its capability for detecting physiological concentrations of sodium and potassium ions is evaluated, with respective sensitivities of 4.26 × 10-4 and 1.06 × 10-4 mg/(dL·RIU). These results confirm the sensor’s potential for compact, label-free, and high-resolution biosensing applications.