I am replicating Si pillars Hyperbolic metamaterials for focusing.
in the attached paper, it is mentioned the source is at 1.24 TH.
when i make the frequency 1.24 THz, the time signal looks weird, and i can not run my simulation.
2-Also, regarding the focusing distance in the Guassian source, Beam options tab.
i do not know how to choose the focusing distance, in the paper they mentioned 0.2 mm , so is the focusing distance in the beam options tab calculated from the source position.