Real time electron dynamics in an interacting vibronic molecular quantum dot

TL;DR

This paper investigates how strong electron-electron and electron-phonon interactions influence the real-time conductance in a molecular quantum dot, revealing oscillations linked to phonon frequencies and Kondo resonance interference.

Contribution

It introduces a time-dependent analysis of conductance in a molecular quantum dot considering both electron-electron and electron-phonon interactions, highlighting oscillatory behavior.

Findings

Conductance shows decaying sinusoidal oscillations at long timescales.

Oscillation amplitude depends on temperature and electron-phonon coupling.

Oscillation frequency matches the phonon frequency.

Abstract

We employ the time-dependent non-crossing approximation to investigate the joint effect of strong electron-electron and electron-phonon interaction on the instantaneous conductance of a single molecule transistor which is abruply moved into the Kondo regime by means of a gate voltage. We find that the instantaneous conductance exhibits decaying sinusoidal oscillations in the long timescale for infinitesimal bias. Ambient temperature and electron-phonon coupling strength influence the amplitude of these oscillations. The frequency of oscillations is found to be equal to the phonon frequency. We argue that the origin of these oscillations can be attributed to the interference between the emerging Kondo resonance and its phonon sidebands. We discuss the effect of finite bias on these oscillations.