Comparison of the sensitivity by SPR in a metal-ITO-BlueP/TMDC structure

A surface plasmon resonance (SPR) sensor based on blue phosphorus (BlueP)/transition metal dichalcogenides (TMDCs) of two-dimensional (2D) materials is proposed to increase the performance. In this sensor, BlueP/TMDCs are coated on indium tin oxide (ITO) and different metals (Au/Ag/Cu) to improve the sensitivity. By optimizing structural parameters, with the BlueP/WS₂ monolayer and Au thin film, the angular sensitivity can reach as high as 226.0°/RIU. The phase sensitivity also can be as high as 3.6001×10⁶deg/RIU with BlueP/MoS₂ 4 layers, 228 nm ITO, and 25 nm Au thin film, which is 6.77 times that of the Au-ITO structure and 54.40 times that of the traditional SPR of Au thin film. The SPR sensor has potential applications in disease diagnosis, drug development, gene sequencing and treatment, environmental monitoring, food safety testing, doping testing, and other fields.