Elena Roxana Racec - Theory of the Fano resonances in two-dimensional quantum systems
Fyrirlesturinn verður haldinn fimmtudaginn 1. október kl. 13:00 í húsnæði Háskólans í Reykjavík, Kringlunni 1 (gamla Mbl. húsinu) í stofu K-5.
Elena Roxana Racec,
Brandenburg University of Technology Cottbus, Germany
Abstract
In the frame of the scattering theory we present a model for calculating the resonances of an open quantum system in a two-dimensional electron gas. The single electron conductance is determined in the the Landauer-B\"uttiker formalism and the origin of the different peaks which appear for a large interval of voltages is explained by computing the poles of the current scattering matrix in the complex energy plane. For isolated resonances a Fano line shape with a complex asymmetry parameter is obtained. In the case of interacting resonances the line shapes become more complex. Some of them can be written as superposition of Fano lines, but, for strong interacting resonances, hybrid modes appear and the resonant peaks can not be approximated anymore using Fano functions. A clear physical meaning of all peaks is revealed by a detailed analysis of the scattering wave functions inside the scattering region.
