Numerical investigation of the spectral transmission characteristics of T-shaped metal nanohole array

Surface plasmon polaritons can manipulate and transmit light fields at the nanoscale, offering a wide range of applications in areas such as optoelectronic detection, optical filtering, novel light sources, and biosensing. This study investigated the transmission enhancement characteristics of conventional nanohole arrays through finite-difference time-domain (FDTD) simulations. Additionally, T-shaped metal nanoholes are designed based on the distinct spectral transmission properties of rectangular holes under varying polarized light conditions. Research has demonstrated that compared with their rectangular counterparts, T-shaped metal nanoholes exhibit polarization selectivity and sharper transmission spectra. Furthermore, this study investigated the impact of different components within the structure of T-shaped metal nanoholes on light field modulation by analyzing the electric field distribution. Finally, the influence of various parameters, such as the period, film thickness, and hole size, on the transmission spectrum of T-shaped metal nanoholes is investigated.