Quantum violations of Thermodynamic Uncertainty Relations in Strongly Coupled Open Quantum Systems

Informations projet

QuTUR

N° de convention de subvention: 101104590

DOI

10.3030/101104590

Projet clôturé

Date de signature de la CE 31 Mars 2023

Date de début 1 Juillet 2023

Date de fin 30 Juin 2025

Financé au titre de

• Marie Skłodowska-Curie Actions (MSCA)

Coût total

Aucune donnée

Contribution de l’UE

€ 222 727,68

Coordonné par

LUNDS UNIVERSITET
Sweden

Periodic Reporting for period 1 - QuTUR (Quantum violations of Thermodynamic Uncertainty Relations in Strongly Coupled Open Quantum Systems)

Période du rapport: 2023-07-01 au 2025-06-30

Résumé du contexte et des objectifs généraux du projet

In stochastic thermodynamics, thermodynamic uncertainty relations (TURs) fundamentally connect the efficiency, power output and reliability of any classical heat engine. These TURs imply that any efficient heat engine operating at finite power output must suffer from large fluctuations in the power output, making the engine unreliable. However, these TURs can be broken in quantum heat engines, allowing them to achieve a quantum thermodynamic advantage regarding their output precision with obvious implications for nano-scale applications.

The overall objective of this project was to theoretically analyze noise in quantum dots in general, and TURs in quantum dot heat engines in particular, aiming to establish a clear understanding for the conditions required to break TURs. This project aimed at directly addressing the theoretically complicated but experimentally realistic parameter regime of both strong tunnel-coupling and strong Coulomb interaction. This is possible because of a new thermodynamic renormalization group method recently developed by the fellow.

Travail effectué depuis le début du projet jusqu’à la fin de la période considérée dans le rapport et principaux résultats atteints jusqu’à présent

The main achievement of this project was to include calculations of noise into a thermodynamic renormalization group method recently developed by the fellow. This method treats interactions within the quantum dot system exactly, and effectively resums contributions to all orders in the tunnel couplings between the quantum dot system and the environment. This allows treating the experimentally important but theoretically notoriously difficult regime of large interactions and large tunnel couplings. Extending this theory to include calculations of noise was highly nontrivial and required deriving a set of new diagrammatic rules. A general numerical implementation of the developed theory was also achieved.

Progrès au-delà de l’état des connaissances et impact potentiel prévu (y compris l’impact socio-économique et les conséquences sociétales plus larges du projet jusqu’à présent)

This project has developed new theoretical methods that go beyond the state-of-the-art and that allows calculating both the current and noise through quantum dot systems that have both strong local electron-electron interactions and strong tunnel coupling to metallic electrodes. This allows the investigation of, for example, noise in strongly correlated systems and thermodynamic uncertainty relations.