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Nonlinear quantum heat transfer in hybrid structures: sufficient conditions for thermal rectification
Lian-Ao Wu1, Claire X Yu, Dvira Segal
1Department of Theoretical Physics and History of Science, University of the Basque Country UPV/EHU and IKERBASQUE, Basque Foundation of Science, Bilbao, Spain.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 13, 2009
Summary
We describe nonlinear heat flow in quantum systems, revealing conditions for thermal rectification. This effect, observed in various systems, arises from molecular or reservoir properties, enabling directional heat transfer.
Area of Science:
- Quantum thermodynamics
- Condensed matter physics
- Nanoscale heat transfer
Background:
- Understanding heat flow in quantum systems is crucial for developing novel thermal devices.
- Nonlinear effects in heat transfer are complex and not fully understood.
- Hybrid quantum systems offer unique platforms for studying fundamental thermal phenomena.
Purpose of the Study:
- To provide a unified description of heat flow in two-terminal hybrid quantum systems.
- To analytically investigate nonlinear heat transfer mechanisms.
- To establish conditions for thermal rectification.
Main Methods:
- Analytical study of heat transfer using simple models.
- Modeling excitation and relaxation of a central subsystem mode.
- Analysis of heat flow between diverse reservoirs (metals, solids, spin baths).
Main Results:
- Demonstrated rich nonlinear current-temperature characteristics.
- Identified molecular anharmonicity and complex reservoir spectra as sources of nonlinearity.
- Established sufficient conditions for thermal rectification in two-terminal junctions.
- Classified rectifiers into Type-A (dissimilar reservoir density of states) and Type-B (identical baths with differing particle statistics).
Conclusions:
- Nonlinear heat flow and thermal rectification are ubiquitous effects.
- These phenomena can be observed in phononic, electronic, and photonic systems.
- The findings pave the way for designing novel thermal management devices.
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