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arXiv · 0803.1646

A metamaterial absorber for the terahertz regime: Design, fabrication and characterization

Hu Tao·Nathan I. Landy·Christopher M. Bingham·Xin Zhang·Richard D. Averitt·Willie J. Padilla
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Abstract

We present a metamaterial that acts as a strongly resonant absorber at terahertz frequencies. Our design consists of a bilayer unit cell which allows for maximization of the absorption through independent tuning of the electrical permittivity and magnetic permeability. An experimental absorptivity of 70% at 1.3 terahertz is demonstrated. We utilize only a single unit cell in the propagation direction, thus achieving an absorption coefficient $\alpha$ = 2000 cm$^{-1}$. These metamaterials are promising candidates as absorbing elements for thermally based THz imaging, due to their relatively low volume, low density, and narrow band response.

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Hu Tao, Nathan I. Landy, Christopher M. Bingham, Xin Zhang, Richard D. Averitt, Willie J. Padilla. 2008-03-11. A metamaterial absorber for the terahertz regime: Design, fabrication and characterization. https://doi.org/10.1364/oe.16.007181

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