Frequency splitting of spoof surface plasmon polariton waves with a metal disc-type device

At terahertz (THz) frequencies, spoof surface plasmon polaritons (SPPs) are guided along a metal surface with an array of holes or gratings. We have proposed metal disctype splitters with a center hole and radially placed gratings for spoof SPP waves. The three-dimensional FDTD method in cylindrical coordinates has been used to show the frequency splitting behavior. In this article, the power propagating in each direction is evaluated using the Poynting vector calculations. At 1 and 1.5 THz, the propagating power is discussed with the illustration of the spoof SPP waves guided along the disc.