Correlation effects in the transport through quantum dots

TL;DR

This paper investigates how finite charging energy U affects charge and heat transport in quantum dots, revealing violations of classical relations like Mott and Wiedemann-Franz laws due to Kondo resonance effects.

Contribution

It provides a detailed analysis of transport properties in correlated quantum dots with finite U, highlighting deviations from classical transport relations at low temperatures.

Findings

Violation of the Mott relation below T_K due to Kondo resonance.

Finite U significantly alters electric and thermal transport properties.

Wiedemann-Franz law validity is checked under various conditions.

Abstract

We study the charge and heat transport through the correlated quantum dot with a finite value of the charging energy U \neq \infty . The Kondo resonance appearing at temperatures below T_K is responsible for several qualitative changes of the electric and thermal transport. We show that under such conditions the semiclassical Mott relation between the thermopower and electric conductivity is violated. We also analyze the other transport properties where a finite charging energy U has a significant influence. They are considered here both, in the limit of small and for arbitrarily large values of the external voltage eV and/or temperature difference. In particular, we check validity of the Wiedemann-Franz law and the semiclassical Mott relation.