I am trying to simulate the propagation of electromagnetic surface waves at the interface of free space, and a material. These surface waves are excited by a plane wave incident on a sharp metallic object near the material/air interface. To inspect the surface waves, I am requesting the electric near-field in and out of the plane of sample, and I expect to see something resembling a spherical wave in the electric field distribution. To simulate the sample. I initially tried using the Half-Planar Green's function method, but I was not able to see any surface waves. The field distributions exponential decayed away from the metallic object with no oscillatory behavior. I then switched to the FEM with the same material and got fields that resemble a surface wave. Any thoughts on why the Green's function method is not producing the same results as the FEM? My initial thought was the discretization of the material in the FEM vs Half-Planar greens function. But this is a hypothesis that I cannot prove which is why I am consulting this forum.
