Subgridding Boundary Conditions to Model Arbitrarily Dispersive Thin Planar Materials

Abstract

In a previous work, we presented a hybrid implicit–explicit Crank–Nicolson finite-difference time-domain method for treatingmultilayered lossy thin slabs. The main advantage of this methodwas its capability to overcome certain late-time stability issues of theconventional surface impedance boundary condition approaches. In thiscommunication, we extend this method to deal with thin slabs havingarbitrarily dispersive profiles. This approach is validated with the analysisof a spherical shell made of a metallic wire mesh whose macroscopicequivalent constitutive parameters are derived from its microscopicstructure. The results for the electric field inside the sphere are comparedagainst the analytical data and show good agreement with them.