6533b830fe1ef96bd1297179
RESEARCH PRODUCT
Gaussian approximations for the exchange-energy functional of current-carrying states: Applications to two-dimensional systems
Esa RäsänenEsa RäsänenE. K. U. GrossE. K. U. GrossStefano Pittalissubject
PhysicsCondensed Matter - Materials ScienceCurrent (mathematics)Strongly Correlated Electrons (cond-mat.str-el)Exchange interactionMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesElectronic structureAtomic and Molecular Physics and OpticsCondensed Matter - Strongly Correlated ElectronsMatrix (mathematics)Simple (abstract algebra)Density functional theoryStatistical physicsLocal-density approximationEnergy functionaldescription
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.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2009-07-01 | Physical Review A |