Variational total energies from Phi and Psi derivable theories
(1999) In International Journal of Modern Physics B 13. p.535-540- Abstract
- The old variational functional for the total energy
of a many-electron system proposed by Luttinger and Ward (LW) in 1960 is
here tested on the electron gas at the level of the GW approximation. Using
a simple non-interacting Green function to evaluate the fuctional we obtain
a correlation energy very close to that of a fully self-consistent $GW$
calculation which, in turn, is very close to that of an elaborate Monte-Carlo
calculation. Encouraged by this success we have gone beyond the LW theory
and constructed a new functional $Psi[G,W]$ having the Green's function $G$
and the screened interaction $W$ as two completely independent variables.
The electronic... (More) - The old variational functional for the total energy
of a many-electron system proposed by Luttinger and Ward (LW) in 1960 is
here tested on the electron gas at the level of the GW approximation. Using
a simple non-interacting Green function to evaluate the fuctional we obtain
a correlation energy very close to that of a fully self-consistent $GW$
calculation which, in turn, is very close to that of an elaborate Monte-Carlo
calculation. Encouraged by this success we have gone beyond the LW theory
and constructed a new functional $Psi[G,W]$ having the Green's function $G$
and the screened interaction $W$ as two completely independent variables.
The electronic self-energy $Sigma$ and the irreducible polarizability $P$
obtains from $Psi$ as functional derivatives with respect to $G$ and
$W$. The new $Psi$ functional allows for an even simpler way of obtaining
accurate correlation energies and, at the $GW$ level, alredy a non-interacting
$G$ and a simple plasmon-pole approximation to $W$ gives almost the same
correlation energy as before. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/925540
- author
- Almbladh, Carl-Olof LU ; von Barth, Ulf LU and van Leeuwen, Robert
- organization
- publishing date
- 1999
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Manybody Theory, Electron correlation
- in
- International Journal of Modern Physics B
- volume
- 13
- pages
- 535 - 540
- publisher
- World Scientific Publishing
- external identifiers
-
- scopus:0001222216
- ISSN
- 0217-9792
- language
- English
- LU publication?
- yes
- id
- 330c4653-02a5-4a3f-a9c2-dddc247450ae (old id 925540)
- date added to LUP
- 2016-04-04 12:03:53
- date last changed
- 2022-03-16 00:08:43
@article{330c4653-02a5-4a3f-a9c2-dddc247450ae,
abstract = {{The old variational functional for the total energy<br/><br>
of a many-electron system proposed by Luttinger and Ward (LW) in 1960 is<br/><br>
here tested on the electron gas at the level of the GW approximation. Using<br/><br>
a simple non-interacting Green function to evaluate the fuctional we obtain<br/><br>
a correlation energy very close to that of a fully self-consistent $GW$<br/><br>
calculation which, in turn, is very close to that of an elaborate Monte-Carlo<br/><br>
calculation. Encouraged by this success we have gone beyond the LW theory<br/><br>
and constructed a new functional $Psi[G,W]$ having the Green's function $G$<br/><br>
and the screened interaction $W$ as two completely independent variables.<br/><br>
The electronic self-energy $Sigma$ and the irreducible polarizability $P$<br/><br>
obtains from $Psi$ as functional derivatives with respect to $G$ and<br/><br>
$W$. The new $Psi$ functional allows for an even simpler way of obtaining<br/><br>
accurate correlation energies and, at the $GW$ level, alredy a non-interacting<br/><br>
$G$ and a simple plasmon-pole approximation to $W$ gives almost the same<br/><br>
correlation energy as before.}},
author = {{Almbladh, Carl-Olof and von Barth, Ulf and van Leeuwen, Robert}},
issn = {{0217-9792}},
keywords = {{Manybody Theory; Electron correlation}},
language = {{eng}},
pages = {{535--540}},
publisher = {{World Scientific Publishing}},
series = {{International Journal of Modern Physics B}},
title = {{Variational total energies from Phi and Psi derivable theories}},
volume = {{13}},
year = {{1999}},
}