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Balancing power, efficiency, and constancy under broken time-reversal symmetry
Ousi Pan1, Zhiqiang Fan1, Shunjie Zhang1
1Xiamen University, Department of Physics, Xiamen, Fujian 361005, China.
Physical Review. E
|July 24, 2026
Summary
This study reveals new trade-offs for thermoelectric systems, showing broken time-reversal symmetry can improve heat engine performance. These findings offer insights into optimizing energy conversion efficiency and power output.
Area of Science:
- Thermodynamics
- Condensed Matter Physics
- Energy Conversion
Background:
- Thermoelectric systems convert heat to electricity.
- Understanding performance limits is crucial for energy technologies.
- Constancy, a measure of heat engine steadiness, is key.
Purpose of the Study:
- Derive trade-off relations between power, efficiency, and constancy.
- Investigate these trade-offs in the linear-response regime.
- Analyze the impact of broken time-reversal symmetry.
Main Methods:
- Derivation of general trade-off relations.
- Analysis within the linear-response regime.
- Quantification of constancy via fluctuations.
Main Results:
- Established universal bounds for efficiency, power, and fluctuations.
- Demonstrated that broken time-reversal symmetry alters fundamental constraints.
- Showcased potential for near-Carnot efficiency with finite power and fluctuations.
Conclusions:
- Broken time-reversal symmetry offers advantages in thermoelectric systems.
- New insights into nonequilibrium thermodynamics and performance limits.
- Potential for novel heat engines outperforming traditional ones.
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