English

Balancing Power, Efficiency, and Constancy under Broken Time-Reversal Symmetry

Statistical Mechanics 2026-04-09 v1

Abstract

We derive general trade-off relations among the power, efficiency, and constancy for two-terminal thermoelectric systems in the linear response regime. Constancy, which quantifies the steadiness of the heat engine, is measured by its fluctuations. The bounds of the efficiency, power and fluctuations are valid even when time-reversal symmetry is broken, revealing how such a symmetry breaking alters the fundamental constraints on steady-state energy conversion. Our results extend and refine previously established universal trade-offs, offering deeper insight into the performance limits in nonequilibrium thermodynamics. Guided by this bound, heat engines with broken time-reversal symmetry can be operated at near-Carnot efficiency while maintaining finite power output and fluctuations, enabling them to outperform their traditional counterparts.

Keywords

Cite

@article{arxiv.2604.07099,
  title  = {Balancing Power, Efficiency, and Constancy under Broken Time-Reversal Symmetry},
  author = {Ousi Pan and Zhiqiang Fan and Shunjie Zhang and Liwei Chen and Jincan Chen and Shanhe Su},
  journal= {arXiv preprint arXiv:2604.07099},
  year   = {2026}
}
R2 v1 2026-07-01T11:59:20.536Z