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arXiv · 1606.01499

Metacoatings for wavelength scale, high NA plano-concave focusing lenses

Mahin Naserpour·Carlos J. Zapata-Rodríguez·Carlos Díaz-Aviñó·Mahdieh Hashemi
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Abstract

We design plano-concave silicon lenses with coupled gradient-index plasmonic metacoatings for ultrawide apertured focusing utilizing a reduced region of $\sim 20 \lambda^2$. The anomalous refraction induced in the planar input side of the lens and in the boundary of the wavelength-scale focal region boosts the curvature of the emerging wavefront, thus significantly enhancing the resolution of the tightly-focused optical wave. The formation of a light tongue with dimensions approaching those of the concave opening is here evidenced. This scheme is expected to have potential applications in optical trapping and detection.

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Mahin Naserpour, Carlos J. Zapata-Rodríguez, Carlos Díaz-Aviñó, Mahdieh Hashemi. 2016-06-05. Metacoatings for wavelength scale, high NA plano-concave focusing lenses. https://doi.org/10.1364/josab.33.002120

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