Enhancing thermodynamic performances and suppressing fluctuations in interacting quantum-dot thermoelectric engines

Quantum dot systems emerge as promising platforms for studying nanoscale thermoelectric effects and quantum fluctuation phenomena. In this work, we investigate the thermodynamic performance of a Coulomb-blockaded quantum dot operating as a quantum heat engine using the quantum master equation approach. By incorporating full counting statistics, we analyze both average transport properties and current fluctuations in this nanoscale system. We demonstrate that electron–electron interactions significantly enhance thermoelectric performance by increasing both the output power and energy conversion efficiency. Furthermore, we show that Coulomb interactions suppress current fluctuations while preserving the validity of the thermodynamic uncertainty relation. Our results provide important insights into the interplay between quantum effects and thermodynamic principles in nanoscale heat engines.