Density-functional Green function theory : dynamical exchange-correlation field in lieu of self-energy
(2025) In Journal of Physics Condensed Matter 37(31).- Abstract
The one-particle Green function of a many-electron system is traditionally formulated within the self-energy picture. A different formalism was recently proposed, in which the self-energy is replaced by a dynamical exchange-correlation field, which acts on the Green function locally in both space and time. It was found that there exists a fundamental quantity, referred to as the dynamical exchange-correlation hole, which can be interpreted as effective density fluctuations induced in a many-electron system when a hole or an electron is introduced into the system, as in photoemission and inverse photoemission experiments. The dynamical exchange-correlation potential is simply the Coulomb potential of this exchange-correlation hole, which... (More)
The one-particle Green function of a many-electron system is traditionally formulated within the self-energy picture. A different formalism was recently proposed, in which the self-energy is replaced by a dynamical exchange-correlation field, which acts on the Green function locally in both space and time. It was found that there exists a fundamental quantity, referred to as the dynamical exchange-correlation hole, which can be interpreted as effective density fluctuations induced in a many-electron system when a hole or an electron is introduced into the system, as in photoemission and inverse photoemission experiments. The dynamical exchange-correlation potential is simply the Coulomb potential of this exchange-correlation hole, which fulfils a sum rule and an exact constraint, identical to those satisfied by the static exchange-correlation hole in density-functional theory. The proposed formalism has been applied to a number of model systems such as the half-filled one-dimensional Hubbard model, the one-dimensional antiferromagnetic Heisenberg model, and the single-impurity Anderson model. The dynamical exchange-correlation hole and field of the homogeneous electron gas have also been studied with the view of constructing a density-functional approximation such as the local-density approximation. The availability of simple but accurate approximations for the exchange-correlation potential would circumvent costly computations of the traditional self-energy. The formalism may also provide new perspectives and insights into the many-body problem.
(Less)
- author
- Aryasetiawan, F. LU
- organization
- publishing date
- 2025-08-08
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- density-functional theory, dynamical exchange-correlation field, Green function, local-density approximation, self-energy
- in
- Journal of Physics Condensed Matter
- volume
- 37
- issue
- 31
- article number
- 313001
- publisher
- IOP Publishing
- external identifiers
-
- scopus:105012040446
- pmid:40664231
- ISSN
- 0953-8984
- DOI
- 10.1088/1361-648X/adf023
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2025 The Author(s). Published by IOP Publishing Ltd.
- id
- 4cb1a890-5edc-487e-8ac5-856b3f74e374
- date added to LUP
- 2025-11-24 13:48:30
- date last changed
- 2025-11-24 13:49:16
@article{4cb1a890-5edc-487e-8ac5-856b3f74e374,
abstract = {{<p>The one-particle Green function of a many-electron system is traditionally formulated within the self-energy picture. A different formalism was recently proposed, in which the self-energy is replaced by a dynamical exchange-correlation field, which acts on the Green function locally in both space and time. It was found that there exists a fundamental quantity, referred to as the dynamical exchange-correlation hole, which can be interpreted as effective density fluctuations induced in a many-electron system when a hole or an electron is introduced into the system, as in photoemission and inverse photoemission experiments. The dynamical exchange-correlation potential is simply the Coulomb potential of this exchange-correlation hole, which fulfils a sum rule and an exact constraint, identical to those satisfied by the static exchange-correlation hole in density-functional theory. The proposed formalism has been applied to a number of model systems such as the half-filled one-dimensional Hubbard model, the one-dimensional antiferromagnetic Heisenberg model, and the single-impurity Anderson model. The dynamical exchange-correlation hole and field of the homogeneous electron gas have also been studied with the view of constructing a density-functional approximation such as the local-density approximation. The availability of simple but accurate approximations for the exchange-correlation potential would circumvent costly computations of the traditional self-energy. The formalism may also provide new perspectives and insights into the many-body problem.</p>}},
author = {{Aryasetiawan, F.}},
issn = {{0953-8984}},
keywords = {{density-functional theory; dynamical exchange-correlation field; Green function; local-density approximation; self-energy}},
language = {{eng}},
month = {{08}},
number = {{31}},
publisher = {{IOP Publishing}},
series = {{Journal of Physics Condensed Matter}},
title = {{Density-functional Green function theory : dynamical exchange-correlation field in lieu of self-energy}},
url = {{http://dx.doi.org/10.1088/1361-648X/adf023}},
doi = {{10.1088/1361-648X/adf023}},
volume = {{37}},
year = {{2025}},
}