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Graphene plasmonics provides a powerful means to extend the reach of metasurface technology to the terahertz spectral region, with the distinct advantage of active tunability. Here we introduce a comprehensive design platform for the development of THz metasurfaces capable of complex wavefront manipulation functionalities, based on ribbon-shaped graphene plasmonic resonators combined with metallic antennas on a vertical cavity. Importantly, this approach is compatible with the electrical characteristics of graphene grown by chemical vapor deposition (CVD), which can provide the required mm-scale dimensions unlike higher-mobility exfoliated samples. We present a single device structure that can be electrically reconfigured to enable multiple functionalities with practical performance metrics, including tunable beam steering and focusing with variable numerical aperture. These capabilities are promising for a significant impact in a wide range of THz technologies for sensing, imaging, and future wireless communications.
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Broadband wide-angle terahertz antenna based on the application of transformation optics to a Luneburg lens
Abstract The design of antennas for terahertz systems remains a significant challenge. These antennas must provide very high gain to overcome significant free-space path loss, which limits their ability to broadcast or receive a beam over a wide angular range. To circumvent this limitation, here we describe a new device concept, based on the application of quasi-conformal transformation optics to the traditional Luneburg lens. This device offers the possibility for wide-angle beam steering and beam reception over a broad bandwidth, scalable to any frequency band in the THz range.
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- PAR ID:
- 10226135
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41598-021-84849-8
