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arXiv · 1204.5422

Evolutionary optimization of optical antennas

Thorsten Feichtner·Oleg Selig·Markus Kiunke·Bert Hecht
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Abstract

The design of nano-antennas is so far mainly inspired by radio-frequency technology. However, material properties and experimental settings need to be reconsidered at optical frequencies, which entails the need for alternative optimal antenna designs. Here a checkerboard-type, initially random array of gold cubes is subjected to evolutionary optimization. To illustrate the power of the approach we demonstrate that by optimizing the near-field intensity enhancement the evolutionary algorithm finds a new antenna geometry, essentially a split-ring/two-wire antenna hybrid which surpasses by far the performance of a conventional gap antenna by shifting the n=1 split-ring resonance into the optical regime.

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Thorsten Feichtner, Oleg Selig, Markus Kiunke, Bert Hecht. 2012-08-20. Evolutionary optimization of optical antennas. https://doi.org/10.1103/physrevlett.109.127701

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