Single-electron approach for time-dependent electron transport

TL;DR

This paper introduces a novel single-electron basis approach to simplify the analysis of time-dependent electron transport in mesoscopic systems, generalizing the Landauer formula for transient and oscillating potentials.

Contribution

It presents a new single-particle basis method that simplifies time-dependent electron transport calculations and extends the Landauer formula to non-stationary regimes.

Findings

Derived an analytical expression for time-dependent resonant current.

Applied the method to quantum dot tunneling with oscillating barriers.

Connected ac current results to electron pumping in the adiabatic limit.

Abstract

We develop a new approach to electron transport in mesoscopic systems by using a particular single-particle basis. Although this basis generates redundant many-particle amplitudes, it greatly simplifies the treatment. By using our method for transport of non-interacting electrons, we generalize the Landauer formula for transient currents and for time-dependent potentials. The result has a very simple form and clear physical interpretation. As an example, we apply it to resonant tunneling through a quantum dot where the tunneling barriers are oscillating in time. We obtain analytical expression for the time-dependent (ac) resonant current. However, in the adiabatic limit this expression displays the dc current for zero bias (electron pumping).