Enabling large-scale nanostructure modeling by Fourier modal method in combination with distributed computing

In many simulations of large optical systems, the requirement on CPU-time and memory renders a simulation of the full system very time consuming or even impossible. A possible solution is the simulation of subsystems and the subsequent stitching of the calculated fields. In distributed computing, stitching may strongly decrease the computation time and the simulation of large systems may become possible. We investigated simulation time and accuracy of the simulations of such systems using the Fourier modal method. For that purpose, we investigated the calculated fields for different boundary conditions and different illuminations by the incident light. For the boundary conditions, we used periodic and absorbing boundaries. The investigated illuminations contain the field that illuminates the full system and restrictions of the illumination to parts of the subsystem. Both points have a significant influence on how large the overlap needs to be to get a desired accuracy.