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arXiv · 1502.06684

Tailoring the slow light behavior in terahertz metasurfaces

Abstract

We experimentally study the effect of near field coupling on the transmission of light in terahertz metasurfaces, possessing slightly distinctive SRR resonances. Our results show that the interplay between the strengths of electric and magnetic dipoles, modulates the amplitude of resulting electromagnetically induced transmission, probed under different types of asymmetries in the coupled system. We employ a two-particle model to theoretically study the influence of the near field coupling between bright and quasi-dark modes on the transmission properties of the coupled system and we find an excellent agreement with our observed results. Adding to the enhanced transmission characteristics, our results provide a deeper insight into the metamaterial analogues of atomic electromagnetically induced transparency and offer an approach to engineer slow light devices, broadband filters and attenuators at terahertz frequencies.

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Manukumara Manjappa, Sher-Yi Chiam, Longqing Cong, Andrew A. Bettiol, Weili Zhang, Ranjan Singh. 2015-02-24. Tailoring the slow light behavior in terahertz metasurfaces. https://doi.org/10.1063/1.4919531

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