I am combing posted topics into a one. I am simulating the scattering from an AFM (Atomic Force Microscope) tip in the THZ frequency range. As a model for my AFM I for this post have used a cone much simpler and very similar to my full simulation. The cone is a rough approximation of an AFM tip without the cantilever. Since the height of the AFM is on the order of the incident wavelengths (~15um), antenna resonances can be seen in the scattered far field. In this way it is sometimes referred to as a nano antenna. What I am really interested in though is placing a dielectric slab beneath the the apex of the cone. As the cone is brought closer to the dielectric, through a near field mediation between cone apex and sample, the scattered far field changes with the introduction of a dielectric. It is possible to unravel this change and determine local optical properties of the underlying dielectric. What I would like to prove is that instead of simulating a platinum coated silicon cone, I can simply replace the multilayer with a PEC. I am simulating my platinum as a dielectric because my meshing requirements near the apex of the cone are such that the skin effect approximation displays errors since the mesh is much smaller than the thickness of the coating. I am afraid to simulate the platinum as a metallic layer for this reason. My first attempt at simulating the multilayered cone was with no dielectric underneath the cone and by placing a smaller cone inside the original cone and simulating the platinum region and silicon dielectric region with the SEP. I am unsure if this is the correct way to go about simulating the platinum/silicon layers so I attempted to use the FEM. But since the effective wavelength in platinum is quite small the meshing requirements for the platinum exceed my computational capacity. Simply put I need to know that I can reliably simulate a PEC instead of the multilayer. Any suggestions?
Unable to find an attachment - read this blog
