## Rigorous and Fast Discrete Dipole Approximation for Particles near a Plane Interface

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posted on 31.12.2015, 00:00 by Maxim A. Yurkin, Marcus HuntemannThe discrete dipole approximation
(DDA) is a widely used method
for simulation of various optical properties of nanoparticles of arbitrary
shape and composition. We present a modification of the DDA to rigorously
treat particles located above the plane homogeneous substrate. The
modification is based on discretization of only the particle itself
and retains the three-dimensional fast Fourier transform acceleration
scheme of the free-space DDA; hence, it has the same order of computational
complexity. It is implemented in the recent version of the open-source
ADDA code, available for anyone to use. The method shows extremely
good accuracy (better than 0.4%) in test simulations of far-field
scattering for spheres and spheroids above transparent and metallic
substrates, using the T-matrix method as a reference. An example of
near-field calculation is presented for a silver sphere on a glass
substrate.