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Updated: Jan 17, 2026
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
15.9K
Random metamaterials with double negative electromagnetic parameters in dense CuCr2Se4-CoCr2Se4 binary spinels.
Jun Cao1, Chengsheng Wang1, Zechao Xu1
1College of Chemical Engineering, State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, P.R. China. lyan@njtech.edu.cn.
Dalton Transactions (Cambridge, England : 2003)
|September 18, 2025
Summary
This study introduces tunable double-negative metamaterials using copper and cobalt chromium selenide composites. These materials exhibit negative permittivity and permeability for advanced electromagnetic applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Electromagnetism
Background:
- Metamaterials with simultaneous negative permittivity (ε < 0) and negative permeability (μ < 0) are crucial for advanced electromagnetic applications.
- Chromium-based selenium spinel composites show potential for double-negative metamaterials (DNMs), but achieving tunable properties is challenging.
Purpose of the Study:
- To synthesize and characterize (1 - x)CuCr2Se4·xCoCr2Se4 composites.
- To achieve and tune double-negative electromagnetic properties in the MHz frequency range.
- To understand the mechanisms behind negative permittivity and permeability in these composites.
Main Methods:
- Solid-state reaction synthesis of (1 - x)CuCr2Se4·xCoCr2Se4 samples.
- Electromagnetic property measurements in the MHz frequency range.
- Analysis using the Drude model and investigation of magnetic resonance phenomena.
Main Results:
- Double-negative properties were observed in specific MHz frequency ranges for varying CoCr2Se4 concentrations (x=0.2, 0.4, 0.6).
- Negative permittivity was attributed to plasma oscillations of delocalized carriers (Drude model).
- Negative permeability resulted from suppressed eddy currents due to low conductivity, enhancing magnetic resonance.
Conclusions:
- The CoCr2Se4 addition effectively modulates the electromagnetic properties of CuCr2Se4-based composites.
- The composite design reduces electromagnetic attenuation and enhances magnetic responsiveness.
- This research advances the understanding and development of single-phase double-negative metamaterials for low-frequency applications.
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