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arXiv · 1701.08221

Experimental Demonstration of >230{\deg} Phase Modulation in Gate-Tunable Graphene-Gold Reconfigurable Mid-Infrared Metasurfaces

Michelle C. Sherrott·Philip W. C. Hon·Katherine T. Fountaine·Juan C. Garcia·Samuel M. Ponti·Victor W. Brar·Luke A. Sweatlock·Harry A. Atwater
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Abstract

Metasurfaces offer significant potential to control far-field light propagation through the engineering of amplitude, polarization, and phase at an interface. We report here phase modulation of an electronically reconfigurable metasurface and demonstrate its utility for mid-infrared beam steering. Using a gate-tunable graphene-gold resonator geometry, we demonstrate highly tunable reflected phase at multiple wavelengths and show up to 237{\deg} phase modulation range at an operating wavelength of 8.50 {\mu}m. We observe a smooth monotonic modulation of phase with applied voltage from 0{\deg} to 206{\deg} at a wavelength of 8.70 {\mu}m. Based on these experimental data, we demonstrate with antenna array calculations an average beam steering efficiency of 50% for reflected light for angles up to 30{\deg}, relative to an ideal metasurface, confirming the suitability of this geometry for reconfigurable mid-infrared beam steering devices.

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Michelle C. Sherrott, Philip W. C. Hon, Katherine T. Fountaine, Juan C. Garcia, Samuel M. Ponti, Victor W. Brar, Luke A. Sweatlock, Harry A. Atwater. 2017-01-27. Experimental Demonstration of >230{\deg} Phase Modulation in Gate-Tunable Graphene-Gold Reconfigurable Mid-Infrared Metasurfaces. https://doi.org/10.1021/acs.nanolett.7b00359

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