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arXiv · 1008.2094

Strong influence of packing density in terahertz metamaterials

Ranjan Singh·Carsten Rockstuhl·Weili Zhang
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Abstract

We investigate the response of terahertz metamaterials made of split-ring resonators depending on the unit cell density. It is shown that the fundamental resonance has its highest Q factor for a period of one-third the resonance wavelength. Increasing or decreasing the period from that optimal period reduces the Q factor. All observations are explained by understanding radiative coupling as the dominant loss mechanism at low densities, whereas the strong inter SRR coupling enhances non-radiative losses at high densities. Our results allow designing metamaterials with adjustable Q factors and possibly suggesting that an optimal package density exists to induce the strongest dispersion.

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Ranjan Singh, Carsten Rockstuhl, Weili Zhang. 2010-08-12. Strong influence of packing density in terahertz metamaterials. https://doi.org/10.1063/1.3525169

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