Events
TITLE | Electron Correlations in Solids |
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TYPE | Distinguished Lectures |
DATE/TIME | 2006-04-24 |
PLACE | APCTP Seminar Room |
SPEAKER | Prof. Peter Fulde |
AFFILIATION | Max Planck Institute for Physics of Complex Systems |
CONTENTS | |
* Title : Electron Correlations in Solids
* Speaker : Prof. Peter Fulde
* Affiliation : Max-Planck Institute for the Physics of Complex Systems, Dresden, Germany
* Date & Time : Apr. 24(Mon), 2006.
* Place : Seminar Room #512, APCTP Headquarters
* Hosted by APCTP, POSTECH
* Abstract
Treating a many-electron system requires appropriate approximations. The simplest one is to assume that due to their mutual Coulomb interactions the electrons experience a self* consistent mean field. In many cases a self* consistent field or Hartree* Fock approximation is not sufficient and one has to include electronic correlations. Their strength depends on the relative size of the Coulomb repulsion energy and the kinetic energy gain due to delocalization. While in elemental semiconductors correlations are not very strong but nevertheless important, this is different in 4f and 5f systems. The latter represent strongly correlated electronic systems which show phenomena like the Kondo effect, charge order, a dual behavior of 5f electrons or more generally heavy quasiparticle excitations. Specific examples of heavy fermion systems will be given. Also wavefunction methods versus density functional theory will be discussed. Last not least it will be shown that for a number of solids one can presently determine the ground-state wavefunction and excited states (energy bands) including correlations with quantum chemical accuracy
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