Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published May 10, 2017 | Submitted + Supplemental Material
Journal Article Open

Experimental Demonstration of >230° Phase Modulation in Gate-Tunable Graphene-Gold Reconfigurable Mid-Infrared Metasurfaces

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° phase modulation range at an operating wavelength of 8.50 μm. We observe a smooth monotonic modulation of phase with applied voltage from 0° to 206° at a wavelength of 8.70 μm. Based on these experimental data, we demonstrate with antenna array calculations an average beam steering efficiency of 23% for reflected light for angles up to 30° for this range of phases, confirming the suitability of this geometry for reconfigurable mid-infrared beam steering devices. By incorporating all non-idealities of the device into the antenna array calculations including absorption losses which could be mitigated, 1% absolute efficiency is achievable up to 30°.

Additional Information

© 2017 American Chemical Society. Received: January 26, 2017; Revised: April 15, 2017; Published: April 26, 2017. This work was supported by the U.S. Department of Energy (DOE) Office of Science, under Grant No. DE-FG02-07ER46405. M.C.S. acknowledges support by the Resnick Sustainability Institute. This research used facilities of the DOE 'Light-Material Interactions in Energy Conversion' Energy Frontier Research Center. Author Contributions: M.C.S. and P.W.C.H. are equal contributors. The authors declare no competing financial interest.

Attached Files

Submitted - 1701.08221.pdf

Supplemental Material - nl7b00359_si_001.pdf

Files

1701.08221.pdf
Files (6.6 MB)
Name Size Download all
md5:631d861e495efbfc7eed8901882cc7ca
5.8 MB Preview Download
md5:2bdc99d994044b3aa50cd6fd85159e23
802.7 kB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 25, 2023