Rigorous and fast computation of plasmonic particle-substrate interactions

Abstract

As powerful wave-front shapers, meta-surfaces can be used as planar lenses, polarizers, vortex generators, and other components. A general design approach is the finite difference time domain (FDTD) technique, which is robust but computationally costly. The discrete dipole approximation (DDA) is a rigorous and fast alternative, but has not been widely used in nanophotonic design because of computational complexity resulting from dipole-substrate interactions. Here we present a substrate-compatible DDA formulation using a one-dimensional Green’s function in cylindrical coordinates that accurately handles singularities and high-frequency oscillations. It is significantly faster with similar accuracy compared to several other methods, including FDTD.