Dynamical Coulomb Blockade and the Derivative Discontinuity of Time-Dependent Density Functional Theory

TL;DR

This paper explores how the exchange-correlation potential discontinuity in density functional theory influences electron transport, revealing a dynamical Coulomb blockade characterized by oscillatory charging and discharging in nanojunctions.

Contribution

It demonstrates a dynamical perspective of Coulomb blockade through time-dependent simulations, linking potential discontinuity to oscillatory electron transport.

Findings

Dynamical Coulomb blockade manifests as current oscillations.

System reaches a non-steady, oscillatory state instead of a steady current.

Correlation effects induce periodic charging and discharging cycles.

Abstract

The role of the discontinuity of the exchange-correlation potential of density functional theory is studied in the context of electron transport and shown to be intimately related to Coulomb blockade. By following the time evolution of an interacting nanojunction attached to biased leads, we find that, instead of evolving to a steady state, the system reaches a dynamical state characterized by correlation-induced current oscillations. Our results establish a dynamical picture of Coulomb blockade manifesting itself as a periodic sequence of charging and discharging of the nanostructure.