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Quantum Bounds on Heat Transport Through Nanojunctions.
1Chemical Physics Theory Group, Department of Chemistry, University of Toronto, 80 Saint George Street, Toronto, Ontario M5S 3H6, Canada.
Physical Review Letters
|July 22, 2015
Summary
We established new quantum mechanical bounds for heat current in nanojunctions. These bounds are valid at high temperatures, even with strong interactions, complementing existing low-temperature limits.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Nanoscale thermodynamics
Background:
- The quantum of thermal conductance (κQ) provides a universal low-temperature bound for heat transport.
- This bound is typically saturated only in systems with non-interacting transport.
Purpose of the Study:
- To derive rigorous quantum mechanical bounds for heat current in nanojunctions.
- To establish bounds applicable at high temperatures, even in the presence of strong interactions.
Main Methods:
- Utilizing exact sum rules to derive quantum mechanical bounds.
- Analyzing heat current through a nanojunction connecting two thermal baths at different temperatures.
Main Results:
- Developed new bounds for heat current that are saturated at high temperatures.
- These bounds remain valid in the quantum regime even for strongly interacting systems.
- Evaluated bounds for harmonic and anharmonic junction models.
Conclusions:
- The derived bounds offer a complementary perspective to existing low-temperature limits.
- These findings are significant for understanding heat transport in nanoscale systems with strong correlations.
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