Gaussian approximations for the exchange-energy functional of current-carrying states: Applications to two-dimensional systems

S. Pittalis, E. Räsänen, E. K. U. Gross

Research output: Contribution to journalArticleScientificpeer-review

23 Citations (Scopus)

Abstract

Electronic structure calculations are routinely carried out within the framework of density-functional theory, often with great success. For electrons in reduced dimensions, however, there is still a need for better approximations to the exchange-correlation energy functional. Furthermore, the need for properly describing current-carrying states represents an additional challenge for the development of approximate functionals. In order to make progress along these directions, we show that simple and efficient expressions for the exchange energy can be obtained by considering the short-range behavior of the one-body spin-density matrix. Applications to several two-dimensional systems confirm the excellent performance of the derived approximations, and verify the gauge-invariance requirement to be of great importance for dealing with current-carrying states.

Original languageEnglish
Article number032515
Number of pages6
JournalPhysical Review A
Volume80
Issue number3
DOIs
Publication statusPublished - Sep 2009
Externally publishedYes
Publication typeA1 Journal article-refereed

Keywords

  • STRONG MAGNETIC-FIELDS
  • DENSITY-MATRIX
  • ELECTRONIC-STRUCTURE
  • GROUND-STATE
  • QUANTUM DOTS
  • DERIVATION
  • MOLECULES
  • OCTOPUS
  • ATOMS
  • TOOL

Cite this