Advanced Dual-Core Photonic Crystal Fiber Plasmonic Biosensor: Unveiling High Sensitivity and Practical Feasibility for Biochemical Detection

The article proposes a dual-core photonic crystal fiber-based plasmonic biosensor. Two prominent hexagonal lattices with circular air holes along with plasmonic material and analyte sensing layer have been deposited on the outer surface of the fiber to make the practical applications feasible. A thickness of 30 nm of noble plasmonic material silver has been applied to excite the surface plasmons. A 5-nm-thin titanium dioxide (TiO₂) layer has also been observed as an adhesive layer between the silica glass and silver. The behavior of the sensor has been examined employing the mode solver-based finite element method (FEM). The proposed sensor gives responses of maximum amplitude sensitivity of 98.67764 RIU⁻¹ and maximum wavelength sensitivity of 14,090 nm/RIU in the y-polarized propagation mode, employing the amplitude and wavelength interrogation methods, respectively. Furthermore, with the variation of concentration of β-LG, it shows maximum amplitude sensitivity of 110.59998 RIU⁻¹ and WS of 5303.253 nm/RIU. Owing to the straightforward design and maximum sensitivity, the proposed sensor can be applicable to detect biological and biochemical samples.