Design and Optimization of a ZnO/Ag/Al₂O₃/Black Phosphorus‐Based Surface Plasmon Resonance Biosensor for Sensitive Detection of Waterborne Bacteria

ABSTRACT In this paper, a novel surface plasmon resonance (SPR) biosensor structure built by zinc oxide (ZnO), silver (Ag), aluminum oxide (Al 2 O 3 ), and black phosphorus (BP) is proposed. The incident light wave wavelength is 632.8 nm. The detection of waterborne bacteria was accomplished through the utilization of the hybrid structure. The transfer matrix method (TMM) is employed to analyze the suggested SPR structure. The angular sensitivity, the figure of merit (FOM), and MR of the proposed construction and other constructions are numerically investigated and compared. To optimize the sensor's performance, the influence of the thickness of each layer on the proposed construction's performance was simulated. Additionally, this study compared the effects on sensitivity, FOM and MR of two‐dimensional materials graphene, WS 2 , and BP. It is found that the proposed sensing structure's highest sensitivity of 187.18 and 252.18 deg RIU −1 with a high figure of merits of 58.31 and 57.97 RIU −1 for V. cholera and E. coli samples detection, respectively. This sensing structure might provide ideas for the construction of precision detection‐suited SPR sensors.