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Calendar of Physics Talks Vienna
| Electronic-structure calculations for correlated materials: Combining FLAPW with DMFT and its application to the Pnictides |
| Speaker: | Dr. Markus Aichhorn (École Polytechnique) |
| Abstract: | During the last decades Density Functional Theory has proven to be a
very powerful method for the prediction of physical properties of
solid-state materials. Nevertheless, due to the necessary
approximations to the unknown exchange-correlation potential, this
theory fails to predict the properties of the very interesting class of
materials with strong electron-electron interactions. One way to
overcome this limitation is the supplementary use of Dynamical
Mean-Field Theory to treat the strong interactions.
In this talk, I will report on a new implementation of the DFT+DMFT
scheme in the framework of a full-potential plane wave method, the
Wien2K package. Its advantage is the high accuracy compared to other
methods commonly used for these kind of calculations.
A very intriguing physical problem, where this method can give an
answer, is the question about the degree of correlations in the
newly-discovered Pnictide superconductors. Our results for LaFeAsO,
one of the parent compounds of the '1111' family, show that these
materials should be regarded as moderately correlated metals with an
effective mass of around 1.8. We also address the discrepancies
between previous calculations on that compound, and discuss the
importance of a reasonable choice of interaction parameters for these
calculations. |
| Date: | Tue, 08.09.2009 |
| Time: | 15:00 |
| Duration: | 60 min |
| Location: | TU Wien, Wiedner Hauptstrasse 8-10, Rote Ber, 138B (7. Stock) |
| Contact: | held@ifp.tuwien.ac.at |
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