Dopant-induced crossover from 1D to 3D charge transport in conjugated polymers

TL;DR

This paper investigates how doping levels induce a transition from one-dimensional to three-dimensional charge transport in conjugated polymers, using frequency-dependent conductivity measurements and a new quantitative model.

Contribution

It introduces a model that explains the doping-induced crossover from 1D to 3D charge transport in conjugated polymers, supported by experimental data.

Findings

High-frequency conductivity dominated by 1D chain transport

Crossover from 1D to 3D conduction with increased doping

Quantitative model accurately describes the transition

Abstract

The interplay between inter- and intra-chain charge transport in bulk polythiophene in the hopping regime has been clarified by studying the conductivity as a function of frequency (up to 3 THz), temperature and doping level. We present a model which quantitatively explains the observed crossover from quasi-one-dimensional transport to three-dimensional hopping conduction with increasing doping level. At high frequencies the conductivity is dominated by charge transport on one-dimensional conducting chains.