One-click electromagnetism at the nanoscale
The substrate's reflections and its higher refractive index red-shift and broaden the plasmon and add a field at the contact; a metal film below a rod creates a strong gap mode.
Yes: any angle of incidence and polarization, and the rod–substrate gap.
Yes: the spheroid's T-matrix is coupled to the substrate's reflection exactly.
A nanorod on glass, silicon or metal: near fields with the substrate, in one click.