The role of disorder on charge transport in molecularly doped polymers and related materials

Borsenberger, P. M.; Magin, E. H.; Auweraer, M. Der Van; Schryver, F. C. De

doi:10.1002/pssa.2211400102

Cited by 175 publications

(170 citation statements)

References 118 publications

Supporting

Mentioning

161

Contrasting

Order By: Relevance

“…In the studies of these MD systems, the observed temperature and electric field dependence is recognized from previously published theoretical and experimental result of charge transport in a Gaussian DOS. 3,36 A comparison with results based on models with only distance dependent transfer integrals shows that the general form of the temperature dependence, given by Eq. (9), remains the same, but the characteristic temperature, T 1 , is notably higher.…”

Section: Discussionmentioning

confidence: 99%

Monte Carlo simulations of charge transport in organic systems with true off-diagonal disorder

Jakobsson

Linares

Stafström

2012

The Journal of Chemical Physics

View full text Add to dashboard Cite

In this work, a novel method to model off-diagonal disorder in organic materials has been developed. The off-diagonal disorder is taken directly from the geometry of the system, which includes both a distance and an orientational dependence on the constituent molecules, and does not rely on a parametric random distribution. The geometry of the system is generated by running molecular dynamics simulations on phenylene-vinylene oligomers packed into boxes. The effect of the kind of randomness generated in this way is then investigated by means of Monte Carlo simulations of the charge transport in these boxes and a comparison is made to the commonly used model of offdiagonal disorder, where only the distance dependence is accounted for. It is shown that this new refined way of treating the disorder has a significant impact on the charge transport, while still being compliant with previously published and confirmed results.

show abstract

Section: Discussionmentioning

confidence: 99%

Monte Carlo simulations of charge transport in organic systems with true off-diagonal disorder

Jakobsson

Linares

Stafström

2012

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…9 There are some indirect experimental results in support of a Gaussian DOS, but the main reason for the trust the GDM has received is its ability to explain a wide range of experimental observations related to charge transport in molecularly doped polymers and conjugated polymers. [9][10][11][12][13][14][15] A characteristic feature of the GDM is a temperature and applied electric field dependence of the mobility, given by…”

Section: Introductionmentioning

confidence: 99%

“…The attempts 13,16,17,[19][20][21] that have been made to explain a maximum or decreasing mobility for an increasing field 12,13,20,22,23 in disordered organic materials as an effect of Marcus theory and its inverted region have in many cases been abandoned in favor of the disorder model. 11,12,20,23,24 The common reason for this is that the parameters needed to fit the analytical expressions given by Eqs. (7) and (8) fall outside the interval of physically reasonable values and therefore, in many cases, the conclusions have been that polaron effects do not play an important role for charge transport in conjugated polymers.…”

Section: Introductionmentioning

confidence: 99%

Polaron effects and electric field dependence of the charge carrier mobility in conjugated polymers

Jakobsson

Stafström

2011

The Journal of Chemical Physics

View full text Add to dashboard Cite

Charge transport in conjugated polymers has been investigated using Monte Carlo simulations implemented on top of the Marcus theory for donor-acceptor transition rates. In particular, polaron effects and the dependency of the mobility on the temperature and the applied electric field have been studied. The conclusions are that while the qualitative temperature dependence is similar to that predicted by Miller-Abrahams theory in the Gaussian disorder model (GDM), the electric field dependence is characterized by a crossover into the Marcus inverted region, not present in the GDM. Furthermore, available analytical approximations to describe the electric field dependence of the mobility in Marcus theory fail to fit the simulation data and hence cannot be used to directly draw conclusions about the importance of polaron effects for charge transport in conjugated polymers.

show abstract

“…The discussion was, to much extent, provoked by the reports on the apparent decrease of the drift mobility with rising electric field at relatively high temperatures and low field strengths in disordered organic materials. 3,4,5,6,7,8,9,10 This apparent decrease of the mobility with increasing electric field was reported to be succeeded by the increase of the mobility at higher field strengths. However, the self-consistent effective-medium theory for drift and diffusion at low electric fields 11 does not show any decrease of the mobility with increasing field.…”

Section: Introductionmentioning

confidence: 94%

Hopping conduction in strong electric fields: Negative differential conductivity

et al. 2008

View full text Add to dashboard Cite

Effects of strong electric fields on hopping conductivity are studied theoretically. Monte-Carlo computer simulations show that the analytical theory of Nguyen and Shklovskii [Solid State Commun. 38, 99 (1981)] provides an accurate description of hopping transport in the limit of very high electric fields and low concentrations of charge carriers as compared to the concentration of localization sites and also at the relative concentration of carriers equal to 0.5. At intermediate concentrations of carriers between 0.1 and 0.5 computer simulations evidence essential deviations from the results of the existing analytical theories.The theory of Nguyen and Shklovskii also predicts a negative differential hopping conductivity at high electric fields. Our numerical calculations confirm this prediction qualitatively. However the field dependence of the drift velocity of charge carriers obtained numerically differs essentially from the one predicted so far. Analytical theory is further developed so that its agreement with numerical results is essentially improved.

show abstract

The role of disorder on charge transport in molecularly doped polymers and related materials

Cited by 175 publications

References 118 publications

Monte Carlo simulations of charge transport in organic systems with true off-diagonal disorder

Monte Carlo simulations of charge transport in organic systems with true off-diagonal disorder

Polaron effects and electric field dependence of the charge carrier mobility in conjugated polymers

Hopping conduction in strong electric fields: Negative differential conductivity

Contact Info

Product

Resources

About