Saved in:
Bibliographic Details
Main Author: Zhao, Zhen
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2408.12216
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912177179328512
author Zhao, Zhen
author_facet Zhao, Zhen
contents We calculate the low-temperature spectral function of the symmetric single impurity Anderson model using a recently proposed dynamical exchange-correlation (xc) field formalism. The xc field, coupled to the one-particle Green's function, is obtained through analytic analysis and numerical extrapolation based on finite clusters. In the Kondo regime, the xc field is modeled by an ansatz that takes into account the different asymptotic behaviors in the small- and large-time regimes. The small-time xc field contributes to the Hubbard side-band, whereas the large-time to the Kondo resonance. We illustrate these features in terms of analytical and numerical calculations for small- and medium-size finite clusters, and in the thermodynamic limit. The results indicate that the xc field formalism provides a good trade-off between accuracy and complexity in solving impurity problems. Consequently, it can significantly reduce the complexity of the many-body problem faced by first-principles approaches to strongly correlated materials.
format Preprint
id arxiv_https___arxiv_org_abs_2408_12216
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Kondo spectral functions at low-temperatures: A dynamical-exchange-correlation-field perspective
Zhao, Zhen
Strongly Correlated Electrons
We calculate the low-temperature spectral function of the symmetric single impurity Anderson model using a recently proposed dynamical exchange-correlation (xc) field formalism. The xc field, coupled to the one-particle Green's function, is obtained through analytic analysis and numerical extrapolation based on finite clusters. In the Kondo regime, the xc field is modeled by an ansatz that takes into account the different asymptotic behaviors in the small- and large-time regimes. The small-time xc field contributes to the Hubbard side-band, whereas the large-time to the Kondo resonance. We illustrate these features in terms of analytical and numerical calculations for small- and medium-size finite clusters, and in the thermodynamic limit. The results indicate that the xc field formalism provides a good trade-off between accuracy and complexity in solving impurity problems. Consequently, it can significantly reduce the complexity of the many-body problem faced by first-principles approaches to strongly correlated materials.
title Kondo spectral functions at low-temperatures: A dynamical-exchange-correlation-field perspective
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2408.12216