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arXiv · 1211.1496

Sub-wavelength focusing meta-lens

Tapashree Roy·Edward T. F. Rogers·Nikolay I. Zheludev
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Abstract

We show that planar a plasmonic metamaterial with spatially variable meta-atom parameters can focus transmitted light into sub-wavelength hot-spots located beyond the near-field of the metamaterial. By nano-structuring a gold film we created an array of meta-lenses generating foci of 160 nm (0.2{\lambda}) in diameter when illuminated by a wavelength of 800 nm. We attribute the occurrence of sub-wavelength hotspots beyond the near field to the phenomenon of superoscillation.

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Tapashree Roy, Edward T. F. Rogers, Nikolay I. Zheludev. 2012-11-07. Sub-wavelength focusing meta-lens. https://doi.org/10.1364/oe.21.007577

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