Efficiency Statistics and Bounds for Systems with Broken Time-Reversal Symmetry

TL;DR

This paper investigates the statistical properties of efficiency in mesoscopic energy transducers that break time-reversal symmetry, revealing how the second law constrains efficiency fluctuations and analyzing specific quantum systems.

Contribution

It introduces universal efficiency statistics for systems with broken time-reversal symmetry and explores the impact of asymmetric Onsager matrices on efficiency distributions.

Findings

Efficiency distribution becomes infinitely broad in the tight-coupling limit with broken symmetry

Second law imposes restrictions on stochastic efficiency statistics

Quantum Hall and triple-quantum-dot systems exemplify the theoretical results

Abstract

Universal properties of the statistics of stochastic efficiency for mesoscopic time-reversal symmetry broken energy transducers are revealed in the Gaussian approximation. We also discuss how the second law of thermodynamics restricts the statistics of stochastic efficiency. The tight-coupling (reversible) limit becomes unfavorable, characterized by an infinitely broad distribution of efficiency at {\em all times}, when time-reversal symmetry breaking leads to an asymmetric Onsager response matrix. The underlying physics is demonstrated through the integer quantum Hall effect and further elaborated in a triple-quantum-dot three-terminal thermoelectric engine.