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arXiv · 1002.1025

Gradient Index Metamaterial Based on Slot Elements

Oliver Paul·Benjamin Reinhard·Bernd Krolla·Rene Beigang·Marco Rahm
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Abstract

We present a gradient-index (GRIN) metamaterial based on an array of annular slots. The structure allows a large variation of the effective refractive index under normal-to-plane incidence and thus enables the construction of GRIN devices consisting of only a small number of functional layers. Using full-wave simulations, we demonstrate the annular slot concept by means of a 3-unit-cell thin GRIN lens for the terahertz (THz) range. In the presented realizations, we achieved an index contrast of Delta n = 1.5 resulting in a highly refractive lens suitable for focusing THz radiation to a spot size smaller than the wavelength.

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Oliver Paul, Benjamin Reinhard, Bernd Krolla, Rene Beigang, Marco Rahm. 2010-02-04. Gradient Index Metamaterial Based on Slot Elements. https://doi.org/10.1063/1.3453758

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