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arXiv · 0909.3323

Temporal coupled-mode theory for Fano resonance in light scattering by a single obstacle

Zhichao Ruan·Shanhui Fan
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Abstract

We present a theory for Fano interference in light scattering by individual obstacle, based on a temporal coupled-mode formalism. This theory is applicable for obstacles that are much smaller than the incident wavelength, or for systems with two-dimensional cylindrical or three-dimensional spherical symmetry. We show that for each angle momentum channel, the Fano interference effect can be modeled by a simple temporal coupled-mode equation, which provides a line shape formula for scattering and absorption cross-section. We validate the analysis with numerical simulations. As an application of the theory, we design a structure that exhibits strong absorption and weak scattering properties at the same frequency.

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Zhichao Ruan, Shanhui Fan. 2009-11-24. Temporal coupled-mode theory for Fano resonance in light scattering by a single obstacle. https://arxiv.org/abs/0909.3323

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