Group seminar Theoretical Physics III

15.11.2017 11 a.m., room: S-439
Dr. Ivan Leonov
Electronic Structure, Magnetic Properties, and Phase Stability of Correlated Materials
22.11.2017 11 a.m., room: S-439
B.Sc. Jakob Bonart
Scaling behavior in confining potentials
29.11.2017 11 a.m., room: S-439
Dr. Gheorghe Lucian Pascut (Rutgers University, USA)
Orbital selectivity and isostructural phase transitions in AMnO3- perovskites
6.12.2017 11 a.m., room: S-439
Dr. Narayan Mohanta
Search for Majorana fermions in artificial heterointerfaces
11.12.2017 12:15 p.m., room: S-439
Prof. Dr. Milos Radonjic (Institute of Physics Belgrade, Serbia)
Phonon anomalies in FeS
Bitte besonderen Termin beachten.
13.12.2017 11 a.m., room: S-439
Dr. Andreas Östlin
Disorder and correlation for realistic materials: a LDA+DMFT and CPA approach
10.1.2018 11 a.m., room: S-439
Priv.-Doz. Dr. Marcus Kollar
On the scaling and statistics of scattering amplitudes
17.1.2018 11 a.m., room: S-439
M.Sc. Marc Alexander
Prethermalization after a short electric field pulse
31.1.2018 11 a.m., room: S-439
Prof. Dr. Ferdi Aryasetiawan (Lund University, Sweden)
Reinterpretation of spectral functions of correlated metals SrVO3 and SrMoO3 according to self-consistent GW+DMFT

The spectral function or density of states of a typical correlated metal is often characterised by a three-peak structure: a quasiparticle peak around the Fermi level sandwiched by two satellite features. These satellite features are usually interpreted as Hubbard bands, which are understood within an atomic picture as arising from a strong onsite Coulomb interaction. We have studied the spectral functions of SrVO3, a prototype of correlated metals as well as SrMoO3 using a newly developed fully self-consistent GW+DMFT scheme. Analysis of the results reveals that the satellite features are better understood as collective plasmon excitations. This conclusion is reached by the finding that after self-consistency is achieved the impurity Hubbard U is substantially screened by the non-local Coulomb interaction and is much smaller than the energy separation between the two satellites, indicating that the conventional Hubbard-band interpretation may not be appropriate. We have also studied a model sodium in which the lattice constant is artificially increased to mimic correlation strength. Indeed, the collective plasmon picture also applies until the lattice constant reaches 1.5 the equilibrium value, at which stage the system turns into a Mott-Hubbard insulator. The present study suggests that the Hubbard band picture may need to be revised in favour of the plasmon picture for a much larger range of correlation strength than what has usually been assumed.

References: [1] L. Boehnke, F. Nilsson, F. Aryasetiawan, and P. Werner, Phys. Rev. B 94, 21106(R) (2016). [2] F. Nilsson, L. Boehnke, P. Werner, and F. Aryasetiawan, Phys. Rev. Mat. 1, 043803 (2017).

7.2.2018 11 a.m., room: S-439
B.Sc. Andreas Weh
Charge reconstruction in magnetic heterostructures