A Novel Plasmonic MIM Sensor Using Integrated 1 × 2 Demultiplexer for Individual Lab-on-Chip Detection of Human Blood Group and Diabetes Level in the Visible to Near-Infrared Region

In this article, we present an innovative plasmonic lab-on-chip (LoC) sensor featuring three ports, utilizing a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1\times2$ </tex-math></inline-formula> demultiplexer to detect two separate samples without cross-contamination. The performance of the sensor is numerically investigated using the finite element method (FEM), yielding a maximum sensitivity of 865.9 nm per refractive index unit (RIU) and a figure of merit (FOM) of 58.4 in the 700–920 nm range. The proposed metal–insulator–metal (MIM) structure, incorporating a diamond-shaped silicon nanodot array with a perimeter of less than 100 nm, serves as a sensing surface, detecting changes in the refractive index (RI) of the surrounding medium. Our suggested sensor demonstrates an extraordinary transmission coefficient (TC) of around −18-dB, it surpasses classical optics…