Dynamical vertex approximation for nanoscopic systems.
With an increasing complexity of nanoscopic systems and the modeling thereof, new theoretical tools are needed for a reliable calculation of complex systems with strong electronic correlations. To this end, we propose a new approach based on the recently introduced dynamical vertex approximation. We demonstrate its reliability already on the one-particle vertex (i.e., dynamical mean field theory) level by comparison with the exact solution. Modeling a quantum point contact with 110 atoms, we show that the contact becomes insulating already before entering the tunneling regime due to a local Mott-Hubbard transition occurring on the atoms which form the point contact.
Valli
A
A
Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria.
Sangiovanni
G
G
Gunnarsson
O
O
Toschi
A
A
Held
K
K