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Controlling the transmitted field into a cylindrical cloak's hidden region
Jeffrey S McGuirk1, Peter J Collins
1Department of Electrical and Computer Engineering, Air Force Institute of Technology, Wright Patterson, OH 45433, USA. jeffrey.mcguirk@afit.edu
Optics Express
|October 30, 2008
Summary
Simplified cylindrical cloaks can reduce scattering, but impedance matching is crucial. Optimizing cloak parameters improves performance and object independence for better cloaking applications.
Area of Science:
- Electromagnetism
- Metamaterials
- Acoustic Cloaking
Background:
- Simplified cylindrical cloaks approximate ideal cloaks but allow energy transmission.
- Existing models inherit power-bending properties but require further refinement.
Purpose of the Study:
- Develop a constraint equation to quantify field behavior matching in simplified cloaks.
- Investigate the trade-offs between internal field reduction and cloak scattering.
Main Methods:
- Derived a constraint equation to evaluate field behavior deviation.
- Analyzed the impact of the micro(theta) parameter on cloak performance.
- Examined impedance matching at the cloak boundary (r=b).
Main Results:
- Reduced deviation from the constraint equation minimizes internal energy transmission.
- Impedance mismatch at r=b creates significant cloak scattering.
- Matched impedance at r=b is more critical than minimizing internal energy for scattering reduction.
Conclusions:
- Optimized cylindrical cloaks require a balance between internal field reduction and boundary impedance matching.
- Cloak performance can be made object-independent by matching impedance and tuning parameters.
- This research offers a path towards more effective and predictable cloaking devices.
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