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arXiv · 1809.09988

Broadband microwave absorption by logarithmic spiral metasurface

Shubo Wang·Bo Hou·C. T. Chan
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Abstract

We propose to use logarithmic spiral resonators for efficient absorption of microwaves. By combining their scale invariant geometries and Fabry-Perot-type resonances stemming from the fundamental TM mode, we realize a microwave metasurface with broadband absorption performance. The metasurface comprises logarithmic spiral resonators backed with a metallic surface and it can absorb >95% of incident microwave energy within the frequency range of 6 GHz - 37 GHz. We discuss the physics underlying the broadband absorption and the crucial role of vortex energy flow. The study opens a new direction of electromagnetic wave absorption by employing the scale invariance of Maxwell equations.

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Shubo Wang, Bo Hou, C. T. Chan. 2018-09-25. Broadband microwave absorption by logarithmic spiral metasurface. https://doi.org/10.1038/s41598-019-50603-4

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