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Twisted moiré conductive thermal metasurface
Huagen Li1, Dong Wang2,3, Guoqiang Xu1
1Department of Electrical and Computer Engineering, National University of Singapore, Kent Ridge, 117583, Republic of Singapore.
Researchers introduce twisted thermotics, a new field analogous to twistronics, to control heat diffusion. Twisting a thermal system allows for switching between heat cloaking and concentration, enabling tunable thermal management.
Area of Science:
- Physics
- Materials Science
- Thermal Engineering
Background:
- Twistronics, based on the moiré magic angle in twisted bilayer graphene, has enabled control over electron properties.
- Opto-twistronics extends these principles to optics, but a thermal analogue remains elusive due to the nature of heat diffusion.
- The concept of a 'magic angle' is ill-defined for heat diffusion, hindering thermal control analogous to electronic or photonic systems.
Purpose of the Study:
- To introduce and experimentally validate a thermal analogue of the magic angle effect for heat diffusion.
- To demonstrate tunable control over heat flow using twisted thermal configurations.
- To establish a new field of 'twisted thermotics' within the broader scope of twistronics.
Main Methods:
- Development of a twisted diffusion system with tailored thermal coupling.
- Experimental validation of heat diffusion manipulation through controlled twisting.
- Observation of functional switching between heat cloaking and concentration effects.
Main Results:
- Successful demonstration of an analog thermal magic angle effect.
- Experimental evidence of switching heat diffusion from cloaking to concentration by twisting the system.
- Validation of twisted thermotics as a viable approach for thermal management.
Conclusions:
- Twisted thermotics offers a novel pathway for precise control over heat diffusion.
- The established principles open avenues for manipulating thermal fields in various configurations, including fluids.
- This work expands the universal applicability of twistronics into the thermal domain, creating new possibilities for thermal engineering.
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