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Updated: Dec 25, 2025

Colloidal Synthesis of Nanopatch Antennas for Applications in Plasmonics and Nanophotonics
Published on: May 28, 2016
Nano-antenna synthesis for an arbitrary far-field radiation pattern and polarization based on vector spherical wave
Abstract:
A systematic method is proposed to synthesize a nano-antenna based on theoretical principles. This nano-antenna, which is composed of a set of small dielectric spheres, is designed to have a desired far-field radiation pattern and polarization. The basis of the proposed method is expanding all electromagnetic waves into the series of vector spherical wave functions. First, the forward problem of calculation of scattering from single and multiple spheres is studied. For cases with more than one sphere, a multiple scattering method is implemented to calculate total scattering. Near-field and far-field waves, absorption, extinction, and differential scattering cross sections are calculated for a single sphere with different sizes and permittivities. Moreover, far-field waves for linear arrays of small spheres are analyzed. All results are validated using an electromagnetic simulation software. Next, the problem of inverse scattering begins by considering a three-dimensional arbitrary pattern and polarization. The aim is to find a set of spheres that generates this pattern. Particle swarm optimization and non-iterative spectral-domain forward scattering methods are combined as a novel method to find the optimal positions of the spheres.
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