Terahertz Square Core Photonic Crystal Fiber Sensor: Revolutionizing Efficient Blood Cell Detection Through Refractive Index Sensing Based on Surface-Enhanced Spectroscopic Properties.

This article recommends a photonic crystal fiber (PCF) with a square hollow core sensor for detecting blood cells effectively. To achieve improved relative sensitivity with low confinement loss (CL), the suggested PCF has been explored in the terahertz (THz) band from 2.0 to 4.0 THz. The Full-Vectorial Finite Element Method (FV-FEM) is used to solve the electromagnetic formula and perform numerical computations on the structure in the THz frequency range domain. At optimal frequency f = 3.2 THz, considerable variations in the relative sensitivity of 91.38%, 92.25%, 93.20%, and 95.48% for glucose, plasma, white blood cell (WBC), and red blood cell (RBC) are revealed. At 3.2 THz, the PCF sensor has a relative sensitivity of 95.5% and CL of 2.3698 × 10−08 dB/m. Furthermore, the photonic crystal fiber has an effective area of 2.9435 × 10−08 m2, a very small EML of 0.00803 cm−1, and a spot size of 1.6626 × 10−04 µm. The relatively small confinement loss (CL), excellent effective mode area, and substantial sensitivity at operating frequency in the THz band (2 THz–4 THz) for each blood component are also investigated in this research. [ABSTRACT FROM AUTHOR]