Analysis of a metal disc-type terahertz surface wave splitter using the cylindrical LOD-FDTD method

To efficiently analyze the electromagnetic problems in cylindrical structures, we develop a locally one-dimensional finite-difference time-domain (FDTD) method in cylindrical coordinates. The Sherman-Morrison formula is used to solve a cyclic matrix, and the image theory is introduced to treat a perfect electric conductor. As an application, we analyze a metal disc-type terahertz surface wave splitter. The computation time is reduced to approximately half that of the explicit FDTD method, while maintaining the comparable accuracy.