Electronic Transport through QD in the whole temperature range including both the high- and the low-T limits with the equation-of-motion technique

TL;DR

This paper theoretically investigates the Kondo effect in quantum dots across all temperature ranges using the equation-of-motion technique, accounting for Coulomb interactions and non-equilibrium effects, and compares well with other advanced methods.

Contribution

It extends the equation-of-motion method to describe the Kondo effect in quantum dots over the entire temperature range, including non-equilibrium conditions.

Findings

Qualitative agreement with NCA, NRG, and NRPT results.

Effective in describing non-equilibrium states under small bias voltage.

Generalizes previous equilibrium results to pseudo-equilibrium conditions.

Abstract

We have studied theoretically the Kondo effect in the quantum dot(QD) within the whole range of temperature by using the equation-of-motion(EOM) technique based on the non-equilibrium Green function formalism. We have taken the finiteness of Coulomb correlation and the non-equilibrium effect into account by calculating the correlation terms emerged from the decoupling approximation using EOM method for the lesser Green function. We showed that the result is in good qualitative agreement with the results of NCA, NRG and NRPT, etc., even using EOM method which is being recognized as a 'conventional' method. The results are the generalization into the pseudo-equilibrium state of the Refs. 32,33 and can be used to describe a non-equilibrium state under the bias voltage which is not so large.