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:
http://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
- ISSN
- 0217-9792
- language
- English
- LU publication?
- yes
- id
- 330c4653-02a5-4a3f-a9c2-dddc247450ae (old id 925540)
- date added to LUP
- 2015-06-20 12:20:46
- date last changed
- 2016-04-16 10:04:26
@misc{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}, keyword = {Manybody Theory,Electron correlation}, language = {eng}, pages = {535--540}, publisher = {ARRAY(0xb417fb8)}, series = {International Journal of Modern Physics B}, title = {Variational total energies from Phi and Psi derivable theories}, volume = {13}, year = {1999}, }