Plasmonic Enhancement Using Yttrium Lithium Fluoride Hybrid Layers in a PCF-Based SPR Sensor for Biomolecule Detection

A high-performance plasmonic surface plasmon resonance (SPR) sensor with a tunable detection range is suggested in this paper. It uses gold (Au) in conjunction with yttrium lithium fluoride (YLiF4) as the adhesive layers, ensuring better sensing performance. We examined the impact of attachment-enhancing material on the sensor’s performance through simulation. According to the results, the AuYLiF4 combination has a maximum wavelength sensitivity (WS) of 24,000 nm/RIU within the analyte refractive index (RI) range of 1.33–1.335 by measuring shifts in their respective resonance wavelengths, which are distinctive at the sensing medium’s RI. Additionally, the proposed sensor attained a maximum amplitude sensitivity (AS) of 848.94 /RIU at RI = 1.33 and a figure of merit (FoM) of 111.6/RIU, achieved at maximum confinement loss. Furthermore, the suggested sensor’s application-oriented sensing performance is examined for blood plasma and krypton, showcasing its capacity to identify minute changes in RI using both wavelength and amplitude interrogation. Other key performance metrics, such as detection accuracy (DA), resolution, and full width at half maximum (FWHM), are also assessed. The sensor’s high sensitivity to analyte RI (1.33,1.335) demonstrates its ability to detect even minute variations in the sensing environment, making it well-suited for precise biomolecule sensing applications.