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Examining and explaining the “generalized laws of reflection and refraction” at metasurface gratings


New article in JOSA A:
Structured metasurfaces enable new possibilities for beam shaping and the miniaturisation of optical elements.
In the literature metasurfaces employing subwavelength structures are commonly related to anomalous reflection and refraction and associated with discontinuities of the wave vector at the interface.
In our article we employ classic diffraction theory to describe the far field diffraction pattern of such structured metasurfaces, define clear limitations for the applicability of generalized reflection and refraction laws and resolve some issues with misleading explanations.
The article supports the understanding of light propagation through subwavelength structured metasurfaces and contains important recommendations how to avoid misleading nomenclature.

The widespread concept of “generalized laws of reflection and refraction” that is commonly applied to wave propagation through metasurfaces is thoroughly explained on the foundation of diffraction theory. This allows definition of strict constraints to the applicability of these generalized laws and highlights the underlying physical effects. A diffraction-based explanation of the reported phenomena is provided that yields a solid theoretical foundation for the prediction of experimental results and that clarifies many of the convoluted explanations found throughout the literature.

Markus Schake: 4.2 Imaging and Wave Optics, PTB-Braunschweig

For further information:
Journal of the Optical Society of America A, Vol. 39, Issue 8, pp. 1352-1359, (2022), doi.org/10.1364/JOSAA.460037

Contact person:
Opens local program for sending emailDr. Markus Schake