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Updated: Oct 9, 2025
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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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Natural Negative-Refractive-Index Materials.
Chih-Yu Chen1,2, Ming-Chien Hsu3, C D Hu1
1National Taiwan University, 106319 Taipei, Taiwan.
Physical Review Letters
|December 22, 2021
Summary
Negative refractive index (NRI), previously exclusive to metamaterials, is now achievable in Dirac semimetals (DSM). This discovery opens new avenues for electromagnetic applications by leveraging unique electron properties in DSM.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Electromagnetism
Background:
- Negative refractive index (NRI) has historically been confined to metamaterials.
- Electrons in Dirac semimetals (DSM) possess unique properties like zero effective mass.
Purpose of the Study:
- To investigate the possibility of achieving NRI in Dirac semimetals (DSM).
- To explore the underlying physical mechanisms responsible for NRI in DSM.
Main Methods:
- Theoretical calculations were performed to analyze electromagnetic responses in DSM.
- The study examined the interplay of quantum vacuum polarization and temperature corrections.
Main Results:
- Calculations confirm the existence of NRI in DSM, a phenomenon not previously observed in such materials.
- NRI in DSM arises from quantum effects and resonance with Dirac cone structures.
- The effect is observable across a broad range of frequencies, including the gigahertz range at room temperature.
Conclusions:
- Dirac semimetals (DSM) offer a novel platform for realizing negative refractive index (NRI) beyond metamaterials.
- The findings suggest potential applications in microwave and optical devices operating at room temperature.
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