Correlated time-dependent transport through a 2D quantum structure

TL;DR

This paper models nonequilibrium magnetotransport in a 2D quantum wire with an embedded ring, revealing how Coulomb interactions and magnetic fields influence electron correlations and transport dynamics.

Contribution

It introduces a generalized master equation approach combined with configuration interaction to analyze interaction effects in a complex quantum structure.

Findings

Coulomb interactions can enhance electron state correlations.

Oscillations in current are caused by correlation dynamics.

External magnetic fields can amplify these oscillations.

Abstract

We use a generalized master equation (GME) to describe the nonequilibrium magnetotransport of interacting electrons through a broad finite quantum wire with an embedded ring structure. The finite quantum wire is weakly coupled to two broad leads acting as reservoirs of electrons. The mutual Coulomb interaction of the electrons is described using a configuration interaction method for the many-electron states of the central system. We report some non-trivial interaction effects both at the level of time-dependent filling of states and on the time-dependent transport. We find that the Coulomb interaction in this non-trivial geometry can enhance the correlation of electronic states in the system and facilitate it's charging in certain circumstances in the weak coupling limit appropriate for the GME. In addition, we find oscillations in the current in the leads due to the correlations oscillations caused by the switched-on lead- system coupling. The oscillations are influenced and can be enhanced by the external magnetic field and the Coulomb interaction.