Thermoelectric cooling of a finite reservoir coupled to a quantum dot

Year: 2024

Authors: Matern S., Moreira S., Samuelsson P., Leijnse M.

Autors Affiliation: Univ Trento, Pitaevskii BEC Ctr, CNR INO, I-38123 Trento, Italy; Univ Trento, Dipartimento Fis, I-38123 Trento, Italy; Lund Univ, NanoLund & Solid State Phys, Box 118, S-22100 Lund, Sweden; Trinity Coll Dublin, Sch Phys, Coll Green, Dublin 2, Ireland; Lund Univ, NanoLund & Math Phys, Box 118, S-22100 Lund, Sweden.

Abstract: We investigate nonequilibrium transport of charge and heat through an interacting quantum dot coupled to a finite electron reservoir. Both the quantum dot and the finite reservoir are coupled to conventional electric contacts, i.e., infinite electron reservoirs, between which a bias voltage can be applied. We develop a phenomenological description of the system, combining a rate equation for transport through the quantum dot with standard expressions for bulk transport between the finite and infinite reservoirs. The finite reservoir is assumed to be in a quasiequilibrium state with a time-dependent chemical potential and temperature which we solve for self-consistently. We show that the finite reservoir can have a large impact on the stationary state transport properties, including a shift and broadening of the Coulomb diamond edges. We also demonstrate that there is a region around the conductance lines where a heat current flows out of the finite reservoir. Our results reveal the dependence of the temperature that can be reached by this thermoelectric cooling on the system parameters, in particular the coupling between the finite and infinite reservoirs and additional heat currents induced by electron-phonon couplings, and can thus serve as a guide for experiments on quantum-dot-enabled thermoelectric cooling of finite electron reservoirs. Finally, we study the full dynamics of the system, with a particular focus on the timescales involved in the thermoelectric cooling.

Journal/Review: PHYSICAL REVIEW B

Volume: 110 (20)      Pages from: 205423-1  to: 205423-9

More Information: We would like to thank V. Svensson and K. Nestmann for insightful discussions. We acknowledge financial support from the Wallenberg Center for Quantum Technologies (WACQT) , the Swedish Research Council (Grant Agreements No. 2020-03412 and No. 2018-03921) , and NanoLund. S.M. acknowledges financial support from the PNRR-MUR project and PE0000023-NQSTI project, cofunded by the European Union-NextGeneration EU, and from Provincia Autonoma di Trento (PAT) . S.V.M. acknowledges fund ing from the Knut and Alice Wallenberg Foundation (Project No. 2016-0089) . This project is cofunded by the European Union (Quantum Flagship project ASPECTS, Grant Agreement No. 101080167) .Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union, Research Executive Agency, or UKRI. Neither the European Union nor UKRI can be held responsible for them.
KeyWords: Transport; Heat; Thermopower; Simulation
DOI: 10.1103/PhysRevB.110.205423