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Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
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THz graphene-integrated metasurface for electrically reconfigurable polarization conversion
Li-Zhao Song1, Andrew Squires1, Timothy van der Laan1
1Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW, Australia.
Nanophotonics (Berlin, Germany)
|December 5, 2024
Summary
This study introduces an electrically reconfigurable terahertz (THz) polarization converter using a graphene-gold metasurface. It demonstrates dynamic control over THz wave polarization for advanced wireless communications and sensing applications.
Area of Science:
- Optics and Photonics
- Materials Science
- Electrical Engineering
Background:
- Terahertz (THz) waves are crucial for future 6G wireless networks, requiring dynamic polarization control for high-capacity communication and sensing.
- Electrical reconfigurability of THz devices remains a significant challenge, hindering technological advancement.
- Graphene-integrated metasurfaces offer a promising platform for manipulating THz wave properties.
Purpose of the Study:
- To develop an electrically reconfigurable THz polarization converter.
- To leverage graphene-gold bilayer metasurfaces for dynamic polarization modulation.
- To demonstrate wide-range electrical tunability of THz polarization states.
Main Methods:
- Fabrication of a graphene-gold bilayer metasurface.
- Investigation of light-matter interaction for polarization conversion.
- Application of external bias voltage for dynamic tuning of reflected polarization states.
Main Results:
- Achieved wide-range electrical tunability of polarization conversion at THz frequencies.
- Demonstrated dynamic modulation of polarization ellipticity from -0.94 to -0.5 at ~240 GHz.
- Showcased polarization angle modulation from 12° to -23° at ~236 GHz.
- Experimentally validated linear-to-circular and linear-to-elliptical polarization conversions.
Conclusions:
- The developed graphene-integrated metasurface enables efficient and electrically tunable THz polarization conversion.
- The device exhibits wide polarization modulation depths, low biasing voltages, and a simple configuration.
- This technology holds significant potential for future THz communication and sensing systems.
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