Dynamical study on polaron formation in a metal/polymer/metal structure

TL;DR

This study models polaron formation in a metal/polymer/metal structure under electric fields, revealing how voltage bias influences electron trapping and barrier reduction at interfaces.

Contribution

It provides a dynamical analysis of polaron formation under electric fields using a tight-binding model, highlighting the effects of voltage bias on electron trapping and interface barriers.

Findings

Polaron forms within hundreds of femtoseconds under bias.

Electric field influences polaron stability and movement.

Applied voltage reduces potential barriers at interfaces.

Abstract

By considering a metal/polymer/metal structure within a tight-binding one-dimensional model, we have investigated the polaron formation in the presence of an electric field. When a sufficient voltage bias is applied to one of the metal electrodes, an electron is injected into the polymer chain, then a self-trapped polaron is formed at a few hundreds of femtoseconds while it moves slowly under a weak electric field (not larger than $% 1.0\times 10^4$ V/cm). At an electric field between $1.0\times 10^4$ V/cm and $% 8.0\times 10^4$ V/cm, the polaron is still formed, since the injected electron is bounded between the interface barriers for quite a long time. It is shown that the electric field applied at the polymer chain reduces effectively the potential barrier in the metal/polymer interface.