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Updated: Aug 25, 2025
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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Magnetically tunable dual-band terahertz absorption based on guided-mode resonance
Applied Optics
|October 18, 2022
Summary
We developed a tunable terahertz absorber using a germanium grating on an InAs substrate. Magnetic fields dynamically adjust absorption peaks, enabling high-resolution terahertz applications.
Area of Science:
- Terahertz (THz) technology
- Metamaterials and Nanophotonics
- Magneto-optics
Background:
- Terahertz (THz) absorbers are crucial for various applications.
- Achieving dynamic tunability in THz absorption remains a challenge.
Purpose of the Study:
- To propose and investigate a magnetically tunable dual-band THz absorber.
- To explore the underlying physical mechanisms for magnetic tunability.
Main Methods:
- Utilizing an Indium Arsenide (InAs) substrate with a subwavelength zero-contrast germanium grating.
- Applying a transverse magnetic field (0.1 Tesla) to tune absorption.
- Investigating magneto-optical and guided-mode resonance effects.
Main Results:
- Demonstrated dynamic tuning of absorption peaks via magnetic field intensity and rotation.
- Achieved absorption intensity up to 99% with a high Q-factor of 258.
- Observed distinct peak shifts at normal and oblique incidence.
Conclusions:
- The proposed structure offers actively adjustable, high-resolution THz absorption.
- This work has implications for nonreciprocal thermal emitters and advanced THz devices.
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