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arXiv · 2010.15624

Temporal Switching to Extend the Bandwidth of Thin Absorbers

Huanan Li·Andrea Alù
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Abstract

Wave absorption in time-invariant, passive thin films is fundamentally limited by a trade-off between bandwidth and overall thickness. In this work, we investigate the use of temporal switching to reduce signal reflections from a thin grounded slab over broader bandwidths. We extend quasi-normal mode theory to time switching, developing an ab initio formalism that can model a broad class of time-switched structures. Our formalism provides optimal switching strategies to maximize the bandwidth over which minimal reflection is achieved, showing promising prospects for time-switched nanophotonic and metamaterial systems to overcome the limits of time-invariant, passive structures.

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Huanan Li, Andrea Alù. 2020-10-29. Temporal Switching to Extend the Bandwidth of Thin Absorbers. https://doi.org/10.1364/optica.408399

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