Charge transport through a molecule driven by a high-frequency field

TL;DR

This paper investigates how a high-frequency external field influences charge transport and noise in a two-site molecular system, revealing controllable noise suppression via external driving parameters.

Contribution

It introduces a high-frequency approximation method to map a time-dependent Hamiltonian to a static one, providing new insights into noise control in molecular electronics.

Findings

Identification of dips in the Fano factor enabling noise control.

Demonstration of the dependence of effective parameters on driving amplitude and frequency.

Explanation of complex noise structures through an intuitive physical picture.

Abstract

We study the current and the associated noise for the transport through a two-site molecule driven by an external oscillating field. Within a high-frequency approximation, the time-dependent Hamiltonian is mapped to a static one with effective parameters that depend on the driving amplitude and frequency. This analysis allows an intuitive physical picture explaining the nontrivial structure found in the noise properties as a function of the driving amplitude. The presence of dips in the Fano factor permits a control of the noise level by means of an appropriate external driving.