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Detecting Thermal Cloaks via Transient Effects
Sophia R Sklan1,2,3, Xue Bai4,5,6, Baowen Li2,3
1Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Scientific Reports
|September 9, 2016
Summary
Researchers show that approximate thermal cloaks, while effective in steady-state, scatter heat over time. This transient heat scattering reveals the cloak
Area of Science:
- Thermal cloaking
- Metamaterials
- Heat transfer
Background:
- Thermal cloaks aim to hide objects from thermal detection.
- Perfect cloaks require inhomogeneous thermal conductivity and heat capacity.
- Approximate cloaks often simplify heat capacity for practical realization.
Purpose of the Study:
- To analyze the detectability of approximate thermal cloaks.
- To investigate the sensitivity of diffusive cloaks to approximations.
- To demonstrate a method for detecting imperfect thermal cloaks.
Main Methods:
- Analytical demonstration of cloak detectability.
- Analysis of transient (time-dependent) heat scattering.
- Experimental construction and detection of an approximate thermal cloak.
Main Results:
- Approximate thermal cloaks are detectable through transient heat scattering.
- Steady-state cloaking is achieved, but transient response is imperfect.
- Experimental detection of an approximate cloak was successful using transient temperature deviations.
Conclusions:
- Approximate thermal cloaks can be detected by analyzing their transient thermal response.
- The presence of a cloak and internal heat sources can be identified.
- Detection is feasible for realizable cloaks with sufficient temperature differences.
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