A Single-Molecule Quantum Heat Engine

TL;DR

This paper demonstrates a molecular-scale quantum heat engine using a single diradical molecule, showing enhanced power and efficiency at low temperatures due to Kondo correlations, advancing miniaturized energy conversion technologies.

Contribution

It introduces a single-molecule quantum heat engine based on particle exchange, highlighting the role of Kondo correlations in improving performance.

Findings

Power output and efficiency are significantly enhanced by Kondo correlations.

Engine reaches up to 53% of the Curzon-Ahlborn efficiency limit.

Operates effectively at low temperatures with extreme miniaturization.

Abstract

Particle-exchange heat engines operate without moving parts or time-dependent driving, relying solely on static energy-selective transport. Here, we realize a particle-exchange quantum heat engine based on a single diradical molecule, only a few nanometers in size. We experimentally investigate its operation at low temperatures and demonstrate that both the power output and efficiency are significantly enhanced by Kondo correlations, reaching up to 53 % of the Curzon-Ahlborn limit. These results establish molecular-scale particle-exchange engines as promising candidates for low-temperature applications where extreme miniaturization and energy efficiency are paramount.