Titanium-Coated Dual-Core D-Shaped SPR-Based PCF for Hemoglobin Sensing

Two new dual-core D-shaped SPR (surface plasmon resonance) PCFs (photonic crystal fibers) (DCD-S-SPR PCF) with a splitting barrier between the twin cores are proposed for the detection and sensing of the different bio-samples of human blood. Moreover, each proposed model is displaying a promising performance for different optical parameters, such as refractive index (RI), confinement loss (αc) birefringence (Bi), coupling length (Lc), transmittance (Tx), wavelength sensitivity (Sw), amplitude sensitivity (Sa), resolution, and figure of merit (FOM). However, the observation is done by the finite element method (FEM) for the assumed wavelength range from 2.1 to 3 μm and provides the comparison between two DCD-S-SPR PCF models. The performance indicator measurements for model 1 and model 2 corresponding to the wavelength sensitivity, amplitude sensitivity, resolution, transmittance variance, FOM, and detection limit of each proposed DCD-S-SPR PCF are, respectively, as follows: 12,320.10 nm/RIU, − 230 RIU−1, 1.5 × 10−2 RIU, 4342.34 dB/RIU, 190, 0.21; and 18,550 nm/RIU, − 360 RIU−1, 1.0 × 10−1 RIU, 6071.42 dB/RIU, 250, 0.07. Also, the satisfactory results of those parameters of each hemoglobin sensor confirm the better sensing performance, and the hemoglobin sensor proves itself a tough competitor in the field of PCF-based bio-sensing application.