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arXiv · 2005.13361

Near-field plates and the near zone of metasurfaces

Roberto Merlin
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Abstract

A brief, tutorial account is given of the differences between the near and far regions of the elec-tromagnetic field emphasizing the source-dependent behavior of the former and the universal properties of the latter. Field patterns of near-field plates, that is, metasurfaces used for sub-wavelength applications, are discussed in some detail. Examples are given of fields that decay away from the plates in an exponential manner, a ubiquitous feature of many interface problems, and metasurfaces for which the decay is not exponential, but algebraic. It is also shown that a properly designed system of two parallel near-field plates can produce fields that exhibit pseudo minima, which are potentially useful for near-field tweezer-like applications.

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Roberto Merlin. 2020-05-27. Near-field plates and the near zone of metasurfaces. https://arxiv.org/abs/2005.13361

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