Simulation of All-dielectric Metasurfaces with Finite Thickness Based on FDTD-GSTC

We propose an effective simulation method of Finite Difference Time Domain-Generalized Sheet Transition Conditions (FDTD-GSTC) for electromagnetic fields from all dielectric metasurfaces with finite thickness. The susceptibilities are introduced in place of physical metasurfaces, which can be calculated from reflection or transmission coefficients with periodic boundary conditions. The standard FDTD-GSTC is only employed for metasurface with zero thickness, in this work, for a metasurface with finite thickness, we characterize it by splitting into several sheets with approximately zero thickness. The continue conditions are enforced between adjacent sheets. Numerical simulation results of the all dielectric metasurface validate the accuracy of the improved method.