König

This project aims at the theoretical description of the dynamics of single electrons in nanodevices in the time domain. The focus on single electrons defines the ultimate conceivable resolution for charge carrier dynamics, provides a convenient platform to study fundamental relaxation processes, and may become relevant for single-electron applications. Nanodevices such as quantum dots are well suited for studying charge carrier dynamics in this ultimate limit since they allow one to address individual electrons, to isolate them from the outside world, to manipulate them in a controlled way by gate voltages, and to study interesting correlations due to Coulomb interaction. The time domain of the charge carrier dynamics can be accessed by making use of external stimuli such as gate pulses. An alternative approach is based on analyzing the full counting statistics of individual charge-transfer events since the full counting statistics provides the maximum information of a dynamic quantum system. The theoretical challenge is, then, to distill out of this full counting statistics the relevant information about the charge dynamics to gain insight into relaxation channels, coherent quantum oscillations, or nonequilibrium many-body states evoked by interaction-induced correlations.

Figure: The charge dynamics in a single-level quantum dot tunnel coupled to one or several electron reservoirs and with large charging energy can be modelled by a three-state system.