September 17, 2009 (Thursday)
2:00 pm in Howey N110

"Quantum tranport in nanostructures"

Kalman Varga
Department of Physics, Vanderbilt University

The quantum transport problem in an infinite open system can be solved in a closed finite system by adding a complex absorbing potential (CAP) to the Hamiltonian deep inside the leads. The efficiency and usefulness of this approach is demonstrated by transport calculations for various systems including metallic wires, carbon nanotube, and molecular junction nanodevices.
One of the major advantage of the CAP approach is that one can also use it to solve time dependent transport problems. The CAP absorbs the outgoing waves and and eliminates the spurious reflections from the boundaries of the computational cell. This allows us to use the time-dependent density functional theory (TDDFT) approach to study electron transport at the nanoscale.