Regensburg 2010 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 60: Poster Session III (Methods: Atomic and electronic structure; Methods: electronic structure theory; Methods: Molecular simulations and statistical mechanics; Methods: Sanning probe techniques; Methods: other (experimental); Methods: other (theory) )

O 60.3: Poster

Mittwoch, 24. März 2010, 17:45–20:30, Poster B2

Optical properties of LiF, NaF and KF based on self-interaction corrected pseudopotentials — •Christoph Sommer, Peter Krüger, and Johannes Pollmann — Institut für Festkörpertheorie, Universität Münster, D-48149 Münster, Germany

Many-body perturbation theory yields optical properties of semiconductors and insulators in good agreement with experiment. In this approach, the Bethe-Salpeter equation is solved for an effective two-particle problem. Very good one-particle excitation energies – as given, e. g., by the GW approximation – are a necessary prerequisite for obtaining reliable results. The GWA is very demanding, however. In turn, self-interaction corrected (SIC) pseudopotential calculations can also provide very accurate electronic energies for ionic wide-band-gap materials. At the same time, they are only about as costly as regular DFT-LDA calculations.

We investigate the applicability of SIC energies and wavefunctions in the Bethe-Salpeter equation using the alkali metal fluorides LiF, NaF and KF as examples. This is done on the basis of SIC pseudopotentials [1] that have been shown to yield bandstructures in good agreement with experiment. We arrive at optical spectra that are in accord with the results available in the literature for these systems.

[1] B. Baumeier, P. Krüger, J. Pollmann, and G. Vajenine, Phys. B 78, 12511 (2008)