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Calendar of Physics Talks Vienna
| DMFT+Sigma approach: methodology and application |
| Speaker: | Igor Nekrasov (Ekaterinburg) |
| Abstract: | his review is devoted to generalization of dynamical mean-field theory
(DMFT)
for strongly correlated electronic systems towards the account of
different types of additional interactions, necessary for
correct physical description of many experimentally observed phenomena
in such systems.
As additional interactions we consider:
(1) interaction of electrons with antiferromagnetic (or charge) fluctuations
of order parameter in high-Tc superconductors leading to the formation
of pseudogap state,
(2) scattering of electrons on static disorder and its role in general
picture of Anderson-Hubbard metal-insulator transition,
(3) electron-phonon interaction and corresponding anomalies of
electronic spectra
in strongly correlated systems.
Proposed DMFT+\Sigma approach is based on taking into account above
mentioned
interactions by introducing additional self-energy \Sigma (in general
momentum dependent)
into conventional DMFT scheme and
calculated in a self-consistent way within the standard set of DMFT
equations
Here we formulate general scheme of calculation of both one-particle
(spectral functions and densities of states) and two-particle
(optical conductivity) properties.
We examine the problem of pseudogap formation, including the
Fermi arc formation and partial destruction of the Fermi surface,
metal-insulator transition in disordered Anderson-Hubbard model,
and general picture of kink formation within electronic spectra
in strongly correlated systems.
DMFT+S approach is generalized to describe realistic materials
with strong electron-electron correlations based on LDA+DMFT method.
General scheme of LDA+DMFT method is presented together with some of its
applications to real systems. The LDA+DMFT+S approach is employed
to modelling of pseudogap state of electron and hole doped high-Tc cuprates.
Comparison with variety of ARPES experiments is given.
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| Date: | Wed, 07.09.2011 |
| Time: | 11:00 |
| Duration: | 45 min |
| Location: | Seminarraum 138C |
| Contact: | Karsten Held |
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