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arXiv · 1812.04899

Constructing the Near field and Far field with Reactive Metagratings: Study on the Degrees of Freedom

Vladislav Popov·Fabrice Boust·Shah Nawaz Burokur
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Abstract

We report that metamaterial-inspired one-dimensional gratings (or metagratings) can be used to control nonpropagating diffraction orders as well as propagating ones. By accurate engineering of the near field, it becomes possible to satisfy power-conservation conditions and achieve perfect control over all propagating diffraction orders with passive and lossless metagratings. We show that each propagating diffraction order requires 2 degrees of freedom represented by passive and lossless loaded thin "wires." This provides a solution to the old problem of power management between diffraction orders created by a grating. The theory developed is verified by both three-dimensional full-wave numerical simulations and experimental measurements, and can be readily applied to the design of wavefront-manipulation devices over the entire electromagnetic spectrum as well as in different fields of physics.

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Vladislav Popov, Fabrice Boust, Shah Nawaz Burokur. 2019-02-27. Constructing the Near field and Far field with Reactive Metagratings: Study on the Degrees of Freedom. https://doi.org/10.1103/physrevapplied.11.024074

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