Transient currents of a single molecular junction with a vibrational mode

TL;DR

This paper investigates the transient electronic currents in a single molecular junction with vibrational coupling, revealing how strong electron-phonon interactions affect the system's nonlinear response over time.

Contribution

It introduces a novel propagation scheme combined with an auxiliary mode expansion to analyze transient dynamics in the Anderson-Holstein model under polaronic conditions.

Findings

Strong electron-phonon interaction significantly alters transient current behavior.

Transient currents exhibit unique characteristics influenced by vibrational modes.

Method effectively captures time-dependent responses after sudden bias changes.

Abstract

By using a propagation scheme for current matrices and an auxiliary mode expansion method, we investigate the transient dynamics of a single molecular junction coupled with a vibrational mode. Our approach is based on the Anderson-Holstein model and the dressed tunneling approximation for the electronic self-energy in the polaronic regime. The time-dependent currents after a sudden switching on the tunneling to leads and an abrupt upward step bias pulse are calculated. We show that the strong electron-phonon interaction greatly influences the nonlinear response properties of the system, and gives rise to interesting characteristics on the time traces of transient currents.