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Cloak based on the angle dependent constitutive parameters tensors.
Optics Express
|October 20, 2015
Summary
Transformation optics cloaks were designed using metamaterials for invisibility. Numerical simulations in the terahertz range confirmed cloaking effectiveness and analyzed the impact of cloak thickness.
Area of Science:
- Metamaterials and Nanophotonics
- Electromagnetism and Optics
Background:
- Transformation optics enables novel electromagnetic wave manipulation.
- Metamaterials offer unique electromagnetic properties not found in natural materials.
- Cloaking devices aim to render objects invisible to electromagnetic waves.
Purpose of the Study:
- To propose and numerically simulate a transformation optics cloak.
- To investigate cloaking performance in the terahertz frequency range.
- To analyze the influence of cloak thickness on invisibility.
Main Methods:
- Design of a cloaking medium using angle-dependent permittivity and permeability tensors.
- Utilizing right-handed and left-handed metamaterial components.
- Numerical simulation via the finite element method (FEM).
- Testing with various wave sources in the terahertz spectrum.
Main Results:
- Successful numerical demonstration of the cloaking effect.
- Terahertz frequency range confirmed as suitable for cloaking.
- Cloaking effectiveness was shown to be dependent on the thickness of the cloaking medium.
Conclusions:
- Transformation optics cloaks are feasible using metamaterials.
- Finite element method simulations are effective for evaluating cloaking performance.
- Cloak thickness is a critical parameter for achieving optimal invisibility.
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