Charge carrier injection into insulating media: single-particle versus mean-field approach

TL;DR

This paper enhances the mean-field model of charge injection into dielectrics by incorporating charge discreteness effects, including image charge and field penetration, to accurately describe various injection regimes.

Contribution

It introduces a modified self-consistent mean-field approach that accounts for charge discreteness and barrier modifications, improving upon existing models for charge injection.

Findings

The model accurately describes both high and low injection regimes.

Comparison with experimental data shows good agreement.

The approach captures barrier lowering effects due to charge discreteness.

Abstract

Self-consistent, mean-field description of charge injection into a dielectric medium is modified to account for discreteness of charge carriers. The improved scheme includes both the Schottky barrier lowering due to the individual image charge and the barrier change due to the field penetration into the injecting electrode that ensures validity of the model at both high and low injection rates including the barrier dominated and the space-charge dominated regimes. Comparison of the theory with experiment on an unipolar ITO/PPV/Au-device is presented.