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arXiv · 1305.5123

Three Dimensional Subwavelength focus by a near-field plate lens

Lu Lan·Wei Jiang·Yungui Ma
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Abstract

We implemented the inverse design method to build a thin near-field lens that could produce a desired subwavelength focus by manipulating the near fields of a magnetic dipole source. The flat near-field lens represented by an artificial impedance surface was fabricated by lumped reactive elements (capacitor and inductor) with spatially varying values. In the experiment a desired annular focusing spot with a characteristic size nearly three times smaller than that allowed by the diffraction limit was obtained. Besides high-resolution imaging, the proposed near-field plate could be extended for other interesting applications, such as wireless power transfer or complex wavefront/beam shaper.

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Lu Lan, Wei Jiang, Yungui Ma. 2013-05-22. Three Dimensional Subwavelength focus by a near-field plate lens. https://doi.org/10.1063/1.4810004

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