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arXiv · 1303.6205

In-Plane Focusing of Terahertz Surface Waves on a Gradient Index Metamaterial Film

Martin F. Volk·Benjamin Reinhard·Jens Neu·René Beigang·Marco Rahm
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Abstract

We designed and implemented a gradient index metasurface for the in-plane focusing of confined terahertz surface waves. We measured the spatial propagation of the surface waves by two-dimensional mapping of the complex electric field using a terahertz near-field spectroscope. The surface waves were focused to a diameter of 500 \micro m after a focal length of approx. 2 mm. In the focus, we measured a field amplitude enhancement of a factor of 3.

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Martin F. Volk, Benjamin Reinhard, Jens Neu, René Beigang, Marco Rahm. 2013-03-25. In-Plane Focusing of Terahertz Surface Waves on a Gradient Index Metamaterial Film. https://doi.org/10.1364/ol.38.002156

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