Metal-insulator-metal waveguide-based optical pressure sensor embedded with arrays of silver nanorods

An optical Metal-Insulator-Metal (MIM) pressure sensor loaded with arrays of silver nanorods (NRs) is proposed in this article. The illustrated sensor contains a straight waveguide coupled with a ladder-shaped resonator. The spectral profile of the proposed schematic is numerically analyzed utilizing the 2D Finite Element Method (FEM). When pressure is exerted upon the silver layer, the resonating area deforms and shifts the resonant wavelength. Extensive computations demonstrate that increasing the deformation shifts the resonant wavelength to the right, establishing a linear relationship. The suggested structure reports maximum pressure sensitivity of 25.4 nm/MPa. Moreover, the impact of NRs on pressure sensitivity is extensively investigated and the results indicate that the designed layout is sensitive to the size and radius of NRs, making it highly tunable. All these features make the modeled prototype a promising nanoscale solution in different fields of engineering.