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Updated: Jun 23, 2025
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
15.3K
Compact coherent perfect absorbers using topological guided-mode resonances.
Chan Young Park1, Ki Young Lee1,2, Yu Sung Choi1
1Department of Physics, Hanyang University, Seoul, 04763, Korea.
Scientific Reports
|June 19, 2024
Summary
We developed a compact topological coherent perfect absorber using guided-mode-resonance gratings. This novel device achieves near-ideal absorption and tight beam confinement, enhancing practical applications.
Area of Science:
- Photonics and Metamaterials
- Topological Physics
Background:
- Guided-mode-resonance (GMR) gratings are key components in optical devices.
- Conventional coherent perfect absorbers often lack compactness and efficient beam matching.
Purpose of the Study:
- To propose a novel topological coherent perfect absorber.
- To achieve near-ideal performance with a compact footprint and tight incident beams.
Main Methods:
- Utilizing a topological junction of two guided-mode-resonance gratings.
- Demonstrating an amorphous silicon thin-film structure.
Main Results:
- Achieved near-perfect absorptance modulation from 1.7% to 99%.
- Demonstrated a compact device footprint of 30 μm.
- Showcased compatibility with 10-μm-wide incident Gaussian beams.
- Enabled tight lateral confinement and near-perfect mode-match to incident beams.
Conclusions:
- The proposed topological approach significantly enhances the practicality of GMR coherent perfect absorbers.
- This method offers robust control over resonance modes and beam coupling.
- The compact and efficient design opens new avenues for optical absorption applications.
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