Zinc Sulfide, Silicon Dioxide, and Black Phosphorus Based Ultra-Sensitive Surface Plasmon Biosensor
Abstract The optical biosensor is the emerging research area in the field of bio-photonics. The black phosphorus zinc sulfide-based hybrid configuration is suitable for implementing and analyzing ultrasensitive biosensors. Ag/Zinc sulfide/silicon dioxide/black phosphorus-based biosensor has been implemented in the proposed work using the modified Kretschmann configuration. The sensitivity improvement of the designed SPR sensor is analyzed in the different arrangements of the layers. The thickness of the layers of all the materials has been optimized. The thickness of the Ag metal layer is optimized and taken as 45 nm. The sensitivity and quality factor measured here is as high as \(664.6^\circ /\text{R}\text{I}\text{U}\) and 200 at 1.37 refractive index—the P-polarized light source of \(633\text{n}\text{m}\) wavelength. The proposed biosensor confirms tremendous growth in terms of sensitivity, detection accuracy, and quality factor compared with the traditional SPR sensors. Zinc sulfide has multiple applications in the sensing fields, like sensors based on UV rays, lasers, and gas.