FullWAVE can be used to compute the transmission spectrum of this structure since the underlying algorithm behind FullWAVE, FDTD, solves Maxwell's equations directly without any physical approximations. To calculate the transmission spectrum using FullWAVE, we will use the waveguide mode that we calculated earlier as a launch excitation.
FDTD is a very rigorous algorithm, and due to this rigorousness can be computationally expensive. For an efficient simulation is therefore very important that the FDTD settings be set correctly: to streamline the design process, FullWAVE built-in settings optimizer can be used to have FullWAVE automatically select optimal FDTD time grid settings.
The computed transmission spectrum from FullWAVE is shown in Fig 5. The peak position in the bandgap is located at 1.5531μm, and matches well with the experimental results in Ref .