Improved HIE-FDTD Method for Simulating Thin Layer Structure in Linear Dispersive Media

To accurately simulate the thin layer of linear dispersive media, an improved 3-D finite-difference time-domain (FDTD) method is proposed. The inclusion of a weak conditionally stabilized hybrid implicit-explicit (HIE) FDTD method overcomes the Courant-Friedrichs–Lewy (CFL) condition. In addition, the piecewise linear recursive convolution (PLRC) method enhances the original HIE-FDTD method, and a unified form of the polarization parameter is employed to simplify the model of linear dispersive media. The improved method reduces computational memory requirements and enhances computational efficiency. Numerical results demonstrate the accuracy and effectiveness of the proposed method when compared with traditional FDTD and the original HIE-FDTD methods. Furthermore, the proposed method can be easily applied to multilayer thin-film systems.