Fano resonance based on a triangular resonator and its application on nanosensing

Fano resonance sensors based on metal-insulator-metal (MIM) waveguide have potential applications in fields such as biology, chemistry, and the environment. Here, a nanosensor based on Fano resonance in an MIM-based isosceles triangular resonator system is proposed and numerically studied by finite element method. Simulation results show that the Fano peak can be easily tuned by adjusting the scale factor and the refractive index within the resonator. Furthermore, we thoroughly analyze the impact of the apex angle, rotation angle, and vertical displacement of the resonator on the transmission spectrum. Finally, the sensing characteristics of the proposed structure are optimized and analyzed, and a high-performance plasmonic sensor with a sensitivity of 1100nm/RIU and the maximum figure of merit of 5.46x109 is obtained. The distinctive attributes of our suggested structure are applicable in the realization of various integrated components for the development of multifunctional high-performance nanophotonics devices.