Electron pair current through the correlated quantum dot

TL;DR

This paper investigates how Coulomb interactions in a quantum dot influence electron pair transport, highlighting the role of charge and spin Kondo effects on current behavior at low temperatures.

Contribution

It introduces a two-component model to describe charge Kondo effects and their impact on electron pair tunneling in correlated quantum dots.

Findings

Charge Kondo effect significantly alters electron pair current.

The auxiliary model captures fluctuations between empty and doubly occupied states.

Transport properties are qualitatively affected by Coulomb interaction signs.

Abstract

We study the charge current transmitted through the correlated quantum dot characterized by a finite magnitude of the Coulomb interaction |U|. At low temperatures the correlations can lead to appearance of the spin (for U>0) or charge (for U<0) Kondo states qualitatively affecting the transport properties. We explore an influence of the charge Kondo effect on the electron pair tunneling introducing the auxiliary two-component model which describes the fluctuations between empty and doubly occupied states of the quantum dot.