Experimental Implementation of Achromatic Multiresonant Metasurface for Broadband Pulse Delay

Abstract

By implementing multiple sharp resonances on a single metasurface, one can combine the strong delay of constituent resonances along with the broad aggregate bandwidth of the resonance ensemble, "tricking" the delay-bandwidth limit. Ensuring that the group delay is spectrally constant across the aggregate bandwidth, we can delay arbitrarily broadband pulses without distortion. Here, we demonstrate a concrete experimental implementation of an achromatic time delay metasurface in reflection by fitting five resonant meta-atoms in a subwavelength unit cell to provide five spectrally interleaved sharp resonances (three electric and two magnetic). The proposed metasurface exploits a solely resonant phase delay, instead of propagating phase accumulation, leading to an ultrathin (λ 0 /19) realization. We successfully design a group delay metasurface in the 10 GHz regime that can delay broadband, 700 MHz Gaussian pulses by 2 ns (20 times the carrier cycle). Subsequent microwave measurements verify the large (>4π) phase span over a wide high-reflection band, highlighting the practical potential of metasurfaces for dispersion control applications that rely on large and broadband phase delays.

3D-Printed Metasurface Units for Potential Energy Harvesting Applications at the 2.4 GHz Frequency Band

“…Up to now, metamaterials and metasurfaces (twodimensional version of metamaterials, consisting of a single plane meta-atoms) have been realized for a great variety of applications, such as electromagnetic shields, polarizers, sensors, electromagnetic beam splitters, broadband pulse delay devices, etc. [3][4][5][6][7]. Among them, metamaterials for energy harvesting applications gain great interest lately [8][9][10], since metamaterials can be designed in appropriate dimensions, to enable full electromagnetic absorption in certain frequency regimes.…”

Broadband Control of Group Delay Using the Brewster Effect in Metafilms

“…Recently, metasurfaces with multiple Lorentzian electric and magnetic resonances have enabled broadband control of the group delay [20,21]. In this study, we * tamayama@vos.nagaokaut.ac.jp demonstrate broadband control of the group delay using the Brewster effect in a single-layer metamaterial with only an electric response.…”

In Situ Customized Illusion Enabled by Global Metasurface Reconstruction

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