Tunable plasmon refractive index sensor and a slow-light device optimized by an improved genetic algorithm based on a MIM waveguide

A structure is proposed in this article consisting of a stub metal–insulator–metal (MIM) waveguide coupled with an embedded T-shaped square ring resonator (ETSRR). The transmission characteristics and magnetic field distribution of the design are analyzed in detail using the finite element method (FEM). Furthermore, the geometric parameters are optimized using an improved genetic algorithm to enhance device performance. The proposed structure is therefore an ideal candidate for realizing a refractive index sensor and slow-light device, with potential applications in various fields such as sensing and communication. Moreover, our study provides valuable insights to the design of surface plasmon polarition (SPP) waveguides with computer assistance.