Nature of Charge Carriers in Disordered Organic Molecular Semiconductors

TL;DR

This paper demonstrates through experiments that polarons, rather than bare electrons, are responsible for charge transport in disordered organic molecular semiconductors, impacting their application in electronic devices.

Contribution

It provides the first experimental evidence that polarons are the charge carriers in disordered organic semiconductors, resolving a longstanding debate.

Findings

Polarons are responsible for charge transport in disordered organic semiconductors.

Experimental evidence supports the polaron model over bare electron models.

Understanding polaron transport can improve device performance.

Abstract

Understanding the charge carrier transport in the disordered organic molecular semiconductors is a fascinating and still unresolved problem in modern condensed-matter physics, yet has an extremely important bearing on their application in ``plastic'' based field effect transistor, light emitting diodes and lasers. The most contentious issue in this subject is the nature of the charge carriers i.e. whether they are bare electrons or dressed electrons, known as polarons. Here we show for the first time, by means of simple experiments that polaron moving in static disorder is responsible for charge carrier transport in disordered molecular semiconductors.