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Published on: February 6, 2014
Delay-bandwidth and delay-loss limitations for cloaking of large objects.
Hila Hashemi1, Baile Zhang, J D Joannopoulos
1Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Physical Review Letters
|September 28, 2010
Summary
Cloaking difficulty increases with object size due to fundamental delay-loss and delay-bandwidth limits. These factors are crucial for scaling up cloaking experiments from wavelength-sized objects.
Area of Science:
- Physics
- Metamaterials
- Electromagnetism
Background:
- Metamaterial cloaking aims to render objects invisible across specific wavelengths.
- Previous research has focused on achieving cloaking for small objects relative to the wavelength.
Purpose of the Study:
- To investigate the fundamental limitations of cloaking, specifically focusing on ground-plane cloaking.
- To analyze how object size relative to wavelength impacts cloaking effectiveness.
Main Methods:
- Utilized a simplified model of ground-plane cloaking.
- Analyzed the effects of delay-loss and delay-bandwidth limitations.
Main Results:
- Demonstrated that cloaking difficulty is fundamentally limited by delay-loss and delay-bandwidth.
- Showed these limitations worsen as the object size increases relative to the wavelength.
Conclusions:
- The scalability of experimental cloaking is constrained by inherent physical limitations.
- Future cloaking research must account for these limitations when scaling beyond wavelength-sized objects.
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