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arXiv · 2606.27218

Plasmonic coated scatterers for tunable coherent perfect absorption

Ali Ghorashi·Ali H. Alhulaymi·A. Douglas Stone
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Abstract

We derive, in closed-form, the surface conductivity required for coated subwavelength-scale spherical and cylindrical scatterers to perfectly absorb incident coherent light of fixed angular momentum. To address the challenge of synthesizing an incident wave of a fixed angular momentum, we analyze two geometries where this physics can be accessed from the far-field: a single coated sphere suspended above a good conducting surface, and an array of dipole-coupled coated cylindrical scatterers. We show that the required complex surface conductivities necessary for coherent perfect absorption over a large bandwidth in the terahertz may be easily achieved in moderately doped graphene.

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Ali Ghorashi, Ali H. Alhulaymi, A. Douglas Stone. 2026-06-25. Plasmonic coated scatterers for tunable coherent perfect absorption. https://arxiv.org/abs/2606.27218

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