The energy-scale-dependent Composite Operator Method for the single-impurity Anderson model

TL;DR

This paper applies a new energy-scale-dependent Composite Operator Method to the single-impurity Anderson model, providing a self-consistent solution that captures Kondo physics with high accuracy and low computational effort.

Contribution

It introduces a self-consistent approach that accurately reproduces known results for the Anderson model across all parameter ranges.

Findings

Reproduces exact results with low numerical effort

Captures Kondo-like peak at low temperatures

Applicable for arbitrary external parameters

Abstract

The recently developed energy-scale-dependent Composite Operator Method is applied to the single-impurity Anderson model. A fully self-consistent solution is given and analyzed. At very low temperatures, the density of states presents, on the top of the high-energy background, a Kondo-like peak whose parameter dependence is discussed in detail. The proposed method reproduces the exact results known in the literature with very low numerical effort and it is applicable for arbitrary values of the external parameters.