Electronic structure calculated ab initio by the many-body GW
Wednesday, 14 December 2011, 14:30
Ground-state properties of materials, such as the atomic structure, the
total energy, the electronic density and the phonon frequencies, can be
investigated from ab initio with high accuracy by density-functional
theory (DFT). On the other hand, DFT cannot describe excited-state
properties such as the bandgap, the bandplot or the excitations sampled in
ARPES spectroscopy. One needs to go beyond.
A possibility is represented by Hedin's GW approximation in the
framework of many-body quantum field theory.
We will present ab initio GW calculations of the electronic structure, the
momentum distribution and the conductance. The presented systems will
range from 3D standard Fermi liquid metals (Na) and more exotic Mott
or excitonic insulators (VO2, TiSe2), to low dimensional systems,
such as 2D graphene, 1D nanowires and 0D organic molecules. Our
results will be compared to ARPES, IXSS, STS and quantum transport