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Toward a cylindrical cloak via inverse homogenization
Tom H Anderson1, Tom G Mackay, Akhlesh Lakhtakia
1School of Mathematics and Maxwell Institute for Mathematical Sciences, University of Edinburgh, Edinburgh, UK.
Summary
This study presents a method for creating effective cylindrical cloaks using homogenized composite materials (HCMs). Controlling particle shape in HCMs enables the necessary anisotropy for achieving cloaking effects.
Area of Science:
- Electromagnetism and Materials Science
- Metamaterial research
Background:
- Cylindrical cloaks are essential for electromagnetic wave manipulation.
- Homogenized composite materials (HCMs) offer a pathway to realize complex material properties.
Purpose of the Study:
- To conceptualize an effective cylindrical cloak using homogenized composite materials.
- To determine the material requirements and fabrication methods for such cloaks.
Main Methods:
- Conceptualizing cloaks as assemblies of local neighborhoods made from HCMs.
- Specifying HCMs as uniaxial dielectric-magnetic materials with positive-definite constitutive dyadics.
- Utilizing the inverse Bruggeman formalism for material parameter estimation.
Main Results:
- HCMs can be derived from simple isotropic dielectric-magnetic materials.
- Oriented spheroidal particles allow for achieving necessary HCM anisotropy.
- The inverse Bruggeman formalism estimates component material shapes, parameters, and volume fractions.
Conclusions:
- Effective cylindrical cloaking is achievable with carefully designed HCMs.
- Control over component particle shape is crucial for realizing cloaking anisotropy.
- The proposed homogenization approach simplifies the realization of advanced cloaking devices.
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