Sensitivity Enhancement of the Surface Plasmon Resonance-Based Gas Sensing by Few Layers of Black Phosphorus

A theoretical gas sensor is proposed using bimetal layers with few black phosphorous (BP) layers. The bimetallic layer of the proposed design gas sensor comprises a (gold-silver) Au-Ag layer and a BP layer. The angular interrogation method is employed to calculate the gas sensor performance parameters in the terminology sensitivity, full width at half maximum (FWHM), detection accuracy (DA), and figure of merit (FoM). The highest sensitivity of 253.89 & DEG;/RIU is obtained with an optimized Au thickness. In addition, the proposed gas sensor can detect the environment (gas analyte) with various refractive indices. The outcome of our improved numerical study shows that the role of a few-layer BP improves performance parameters compared to a conventional gas sensor. Therefore, with a LiF prism, the proposed gas sensor can better detect various gases sensing at a wavelength of 633 nm. The gas sensor's performance is high at various refractive indices for the gas analyte (1-1.07). The proposed gas sensor can offer better performance than existing gas sensors.