Advanced

Optical potentials and damped one-electron functions in photoemission and electron scattering

Hedin, Lars LU (1990) In Journal of electron spectroscopy and related phenomena 51. p.102-91
Abstract
Recently a new approach to photoemission, EXAFS and electron scattering has been developed. The correlations between target electrons are separated from the active electron-target electron correlations, and the damping effects are coming out explicitly. The theory uses van Hove diagonal Green's functions and projection operator techniques, not the usual diagram expansions. By omitting from the start terms in the Hamiltonian which lead to reabsorption of the active electron (photoelectron or scattered electron), remarkably simple expressions are obtained. These expressions contain optical potentials which damp the electron propagation, and “fluctuation potentials” which determine the inelastic scattering. The fluctuation potentials also... (More)
Recently a new approach to photoemission, EXAFS and electron scattering has been developed. The correlations between target electrons are separated from the active electron-target electron correlations, and the damping effects are coming out explicitly. The theory uses van Hove diagonal Green's functions and projection operator techniques, not the usual diagram expansions. By omitting from the start terms in the Hamiltonian which lead to reabsorption of the active electron (photoelectron or scattered electron), remarkably simple expressions are obtained. These expressions contain optical potentials which damp the electron propagation, and “fluctuation potentials” which determine the inelastic scattering. The fluctuation potentials also appear in the expressions for the optical potentials. On the RPA level of approximation the fluctuation potentials are obtained from the dielectric response function of the target. The theory is quite general, but its main advantages are for extended systems, where the damped propagators and damped one electron functions are important effects. The present theory should make it possible to quantitatively attack a number of correlation effects in different spectroscopies. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of electron spectroscopy and related phenomena
volume
51
pages
102 - 91
external identifiers
  • Scopus:0345249054
DOI
10.1016/0368-2048(90)80144-Y
language
English
LU publication?
yes
id
79d7024a-909b-4545-86d0-c283a92aacc6 (old id 8821021)
date added to LUP
2016-03-01 09:40:49
date last changed
2016-04-16 11:39:32
@misc{79d7024a-909b-4545-86d0-c283a92aacc6,
  abstract     = {Recently a new approach to photoemission, EXAFS and electron scattering has been developed. The correlations between target electrons are separated from the active electron-target electron correlations, and the damping effects are coming out explicitly. The theory uses van Hove diagonal Green's functions and projection operator techniques, not the usual diagram expansions. By omitting from the start terms in the Hamiltonian which lead to reabsorption of the active electron (photoelectron or scattered electron), remarkably simple expressions are obtained. These expressions contain optical potentials which damp the electron propagation, and “fluctuation potentials” which determine the inelastic scattering. The fluctuation potentials also appear in the expressions for the optical potentials. On the RPA level of approximation the fluctuation potentials are obtained from the dielectric response function of the target. The theory is quite general, but its main advantages are for extended systems, where the damped propagators and damped one electron functions are important effects. The present theory should make it possible to quantitatively attack a number of correlation effects in different spectroscopies.},
  author       = {Hedin, Lars},
  language     = {eng},
  pages        = {102--91},
  series       = {Journal of electron spectroscopy and related phenomena},
  title        = {Optical potentials and damped one-electron functions in photoemission and electron scattering},
  url          = {http://dx.doi.org/10.1016/0368-2048(90)80144-Y},
  volume       = {51},
  year         = {1990},
}