Lindblad theory for incoherently-driven electron transport in molecular nanojunctions

TL;DR

This paper develops a Lindblad quantum master equation approach to model incoherent electron transport in molecular nanojunctions, capturing key phenomena like Coulomb blockade and light emission.

Contribution

It introduces a general Lindblad-based framework for incoherent electron transport, reproducing known conductance features and predicting light-induced currents.

Findings

Lindblad theory reproduces negative differential conductance and Coulomb blockade.

Light-induced currents are predicted in two-site configurations with incoherent driving.

The approach can be extended to include coherent light-matter interactions.

Abstract

We study electron transport in molecular nanojunctions that are driven by incoherent radiation using Markovian quantum dynamics based on the Lindblad quantum master equation. General expressions for the transient electron and photon currents between system and reservoir are derived. For experimentally relevant nanojunction configurations that include on-site Coulomb repulsion, electron tunneling, spontaneous photon emission, and incoherent driving, we show that Lindblad theory can reproduce stationary conductance features reported in the literature such as negative differential conductance, Coulomb blockade, and current-induced light emission. Light-induced currents are predicted for two-site configurations with ground-level tunneling when the incoherent driving rate is comparable with the transfer rate to contact electrodes. Model extensions to include coherent light-matter interaction are suggested.