Self-consistent analytic scattering theory for apertureless THz near-field microscope

We propose a self-consistent analytic scattering theory for apertureless THz near-field microscope (NFM) which is based on an exact image theory. In this new scattering theory, a quasi-electrostatic image theory is adopted to include the effects of the specular reflection of the incident field and the exact image dipoles induced in the probe tip and the sample substrate. The analytic results from our self-consistent theory are in good agreement with the simulation results obtained by using HFSS, a commercial software based on finite element method.