Non-equilibrium Kondo effect in asymmetrically coupled quantum dot

TL;DR

This paper investigates how asymmetrical coupling in quantum dots influences the non-equilibrium Kondo effect, revealing the significance of coupling asymmetry for Kondo peak formation at nonzero voltages.

Contribution

It provides a theoretical analysis of the non-equilibrium Kondo effect in asymmetrically coupled quantum dots using EOM and NCA methods within the Anderson model.

Findings

Asymmetry affects Kondo peak appearance at nonzero voltages

Theoretical results align with recent experimental observations

Highlights importance of coupling asymmetry in quantum dot transport

Abstract

The quantum dot asymmetrically coupled to the external leads has been analysed theoretically by means of the equation of motion (EOM) technique and the non-crossing approximation (NCA). The system has been described by the single impurity Anderson model. To calculate the conductance across the device the non-equilibrium Green's function technique has been used. The obtained results show the importance of the asymmetry of the coupling for the appearance of the Kondo peak at nonzero voltages and qualitatively explain recent experiments.