Sensitivity enhancement of surface plasmon resonance sensor using 2D material barium titanate and black phosphorus over the bimetallic layer of Au, Ag, and Cu

A unique surface plasmon resonance (SPR) biosensors is proposed computationally in this paper, combining recently developed Perovskite (e.g., BaTiO3) with 2D materials (e.g., black phosphorus) atop of standard SPR biosensors. The performance of the proposed structure, such as sensitivity, the figure of merit (FOM), and the quality factor (QF) of the sensors, are evaluated using the attenuated total reflection (ATR) approach. The Ag/BaTiO3/BP, Au/BaTiO3/BP and Cu/BaTiO3/BP structures, respectively, have exceptionally high sensitivity of 360/RIU, 299/RIU, and 378/RIU, which are 1.5, 0.55, and 1.86 times greater than the conventional silver (Ag), gold (Au), copper (Cu) based sensors, with equivalent FOM and QF. For the bimetallic layer first metal Ag, Au, and Cu-based sensors, the thickness of Ag/Au/Cu is 50/40/35 nm, and the thickness of the second metal layer is 10 nm, and the number of BP layers is 0.34 for Ag/Au/Cu-based sensors. BaTiO3 is employed in all cases with an optimum thickness of 5 nm. The proposed biosensors' remarkable performance will pave the road for their implementation in future medical diagnostics and biological detection applications.