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Updated: Jan 9, 2026
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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
15.8K
17-GHz lossless InP-membrane active metasurface
Taichiro Fukui1, Kei Sumita1, Hiroki Miyano1
1Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Science Advances
|December 5, 2025
Summary
Researchers developed a novel active metasurface for ultrafast light control. This device achieves a record 17.5 GHz modulation bandwidth with low optical loss, advancing optical communication and computing.
Area of Science:
- Photonics and Metamaterials
- Optoelectronics
Background:
- Active metasurfaces offer precise spatiotemporal light control for advanced applications.
- Previous devices faced a conductivity-loss trade-off, limiting speed and performance.
- Achieving high-speed, low-loss active metasurfaces is crucial for next-generation optical systems.
Purpose of the Study:
- To experimentally demonstrate a high-speed, low-loss active metasurface.
- To overcome the limitations of existing active metasurface technologies.
- To enable spatiotemporal light control beyond the GHz regime.
Main Methods:
- Utilized an indium phosphide (InP) membrane platform for device fabrication.
- Integrated a high-quality (Q) Friedrich-Wintgen quasi-bound-state-in-the-continuum mode within an InP-membrane high-contrast grating (InP HCG).
- Employed an InP HCG as an ultralow-resistance interdigitated electrode for electrical modulation.
Main Results:
- Achieved a record 17.5 GHz modulation bandwidth at a 1.5-μm wavelength.
- Maintained a high Q factor of 102 and ultralow optical loss of 0.56 dB.
- Demonstrated 50-fold faster modulation compared to silicon-based devices.
Conclusions:
- The InP membrane platform simultaneously provides high electron mobility and low free-carrier absorption.
- The developed active metasurface significantly enhances modulation speed and reduces optical loss.
- This breakthrough paves the way for active metasurfaces operating beyond the GHz regime for diverse optical applications.
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