
Andreas Wacker
Professor

Violating the thermodynamic uncertainty relation in the three-level maser
Author
Summary, in English
Nanoscale heat engines are subject to large fluctuations which affect their precision. The thermodynamic uncertainty relation (TUR) provides a trade-off between output power, fluctuations, and entropic cost. This trade-off may be overcome by systems exhibiting quantum coherence. This Letter provides a study of the TUR in a prototypical quantum heat engine, the Scovil–Schulz-DuBois maser. Comparison with a classical reference system allows us to determine the effect of quantum coherence on the performance of the heat engine. We identify analytically regions where coherence suppresses fluctuations, implying a quantum advantage, as well as regions where fluctuations are enhanced by coherence. This quantum effect cannot be anticipated from the off-diagonal elements of the density matrix. Because the fluctuations are not encoded in the steady state alone, TUR violations are a consequence of coherence that goes beyond steady-state coherence. While the system violates the conventional TUR, it adheres to a recent formulation of a quantum TUR. We further show that parameters where the engine operates close to the conventional limit are prevalent and TUR violations in the quantum model are not uncommon.
Department/s
- Mathematical Physics
- NanoLund: Center for Nanoscience
Publishing year
2021
Language
English
Publication/Series
Physical Review E
Volume
104
Issue
1
Document type
Journal article
Publisher
American Physical Society
Topic
- Physical Sciences
Status
Published
Project
- KAW Project: Nanothermodynamics for optoelectronic semiconductor devices
ISBN/ISSN/Other
- ISSN: 2470-0045