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arXiv · 1605.09277

Towards negative index self-assembled metamaterials

Martin Fruhnert·Stefan Mühlig·Falk Lederer·Carsten Rockstuhl
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Abstract

We investigate the magnetic response of meta-atoms that can be fabricated by a bottom-up technique. Usually such meta-atoms consist of a dielectric core surrounded by a large number of solid metallic nanoparticles. In contrast to those meta-atoms considered thus far, we study here for the first time hollow metallic nanoparticles (shells). In doing so we solve one of the most pertinent problems of current self-assembled metamaterials, namely implementing meta-atoms with sufficiently large resonance strength and small absorption. Both conditions have to be met for deep sub-wavelength meta-atoms to obtain effectively homogeneous metamaterials which may be meaningfully described by negative material parameters. Eventually we show that by using these findings self-assembled negative index materials come in reach.

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Martin Fruhnert, Stefan Mühlig, Falk Lederer, Carsten Rockstuhl. 2016-05-30. Towards negative index self-assembled metamaterials. https://doi.org/10.1103/physrevb.89.075408

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