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arXiv · 2212.05393

Light Scattering on Two Parallel Subwavelength Cylinders

Abstract

The plasmon resonance has found important application in various systems, e.g., nanoantennas, solar panels, refractive index sensors. Unfortunately, a few analytical solutions for such systems are known. The work aims to find a solution for scattering by a plane electromagnetic wave on two parallel cylinders. When their diameters and the gap between them are less than the radiation wavelength, the quasistatic approximation is valid. We build up a conformal transformation that maps Cartesian into bipolar orthogonal coordinates and represent the scattered field as a decomposition by eigenfunctions of the Laplace operator. The near-field intensity distribution is shown to coincide with numerical calculation performed by COMSOL Multiphysics. Green's function obtained allows one to find also higher decomposition orders. Compared to previous studies, we treat the general case of cylinders with different diameters and dielectric constants.

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Alex Verevkin, Alex Bereza, David Shapiro. 2022-12-11. Light Scattering on Two Parallel Subwavelength Cylinders. https://arxiv.org/abs/2212.05393

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