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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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Ultra-wideband antireflection assisted by a continuously varying temporal medium
Optics Express
|October 27, 2022
Summary
We developed an ultra-wideband antireflection temporal medium using multi-stage temporal permittivity variations. This enables reflectionless electromagnetic wave propagation between different materials, validated by impedance matching applications.
Area of Science:
- Electromagnetics
- Materials Science
- Wave Propagation
Background:
- Achieving reflectionless propagation of electromagnetic waves between dissimilar materials is crucial for efficient energy transfer.
- Existing antireflection techniques often suffer from narrow bandwidth limitations.
Purpose of the Study:
- To design and demonstrate an ultra-wideband antireflection temporal medium.
- To enable reflectionless propagation of electromagnetic waves across a broad frequency range.
Main Methods:
- Designing a temporal medium with multi-stage variation of permittivity in the time domain.
- Utilizing a cascaded quarter-wave temporal coating structure.
- Analytical discussion and numerical verification of the proposed strategy.
Main Results:
- Demonstrated ultra-wideband antireflection properties of the designed temporal medium.
- Showcased continuous temporal variation of material constitutive parameters for broadband performance.
- Successfully realized impedance matching between a dielectric slab and free space.
Conclusions:
- The proposed multi-stage temporal medium effectively achieves ultra-wideband antireflection.
- This approach offers a novel method for overcoming bandwidth limitations in antireflection technologies.
- The findings have potential applications in advanced optical and electromagnetic devices.
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