Electronic Transport in Fullerene C20 Bridge Assisted by Molecular Vibrations

TL;DR

This study explores how molecular vibrations influence electronic transport in a C20 fullerene bridge, revealing conductance steps at specific vibrational energies and proposing a new method to control molecular motion via gate voltage.

Contribution

It introduces a combined theoretical approach to analyze vibrational effects on transport in the smallest fullerene, highlighting mode-dependent conductance features and control mechanisms.

Findings

Conductance exhibits large steps at vibrational energies.

Step magnitude varies with vibrational mode and electronic states.

Gate voltage can be used to control molecular vibrations.

Abstract

The effect of molecular vibrations on electronic transport is investigated with the smallest fullerene C20 bridge, utilizing the Keldysh nonequilibrium Green's function techniques combined with the tight-binding molecular-dynamics method. Large discontinuous steps appear in the differential conductance when the applied bias-voltage matches particular vibrational energies. The magnitude of the step is found to vary considerably with the vibrational mode and to depend on the local electronic states besides the strength of electron-vibration coupling. On the basis of this finding, a novel way to control the molecular motion by adjusting the gate voltage is proposed.