Fig. 6.2 — Discrete dipole approximation

Discrete dipole approximation: The particles with which the incoming electromagnetic wave interacts are approximated by a series of discrete dipoles, which must be much smaller than the incoming wavelength. In this picture, we show (a) a spherical nanoparticle, (b) a nanorod and (c) a bow tie nanoantenna approximated using spherical dipoles (spheres).