Electron transport characteristics in nanosegregated columnar phases of perylene tetracarboxylic bisimide derivatives bearing oligosiloxane chains

An electron transport process in columnar phases of perylene tetracarboxylic bisimide derivatives is analyzed based on the one-dimensional Gaussian disorder model.

TRANSIT TIME DISTRIBUTION AND MOBILITY IN MONTE CARLO SIMULATIONS OF THE GAUSSIAN DISORDER MODEL

We study the distribution of transit times in Monte Carlo simulations of the Gaussian disorder model (GDM). The GDM is one of the most successful models to describe the charge transport in random organic materials. The transit time is the time it takes for a charge carrier to travel across a sample. We find that the distribution of transit times over many charge carriers and over different realizations of Gaussian energies shows a heavy tail in the long time limit at low temperatures. This heavy tail can be described by a power law with an exponent that depends on temperature. This sets a limitation on the calculation of mobility of charge carriers using an average transit time at low temperatures. We discuss the implication of these results on dispersive transport.

Unification of the Charge Transport in Field-Effect Transistors and Light-Emitting Diodes Based on Organic Semiconductors

A physically based mathematical model for the charge transport in field-effect transistors and lighting-emitting diodes based on disordered organic semiconductors has been presented. It is developed basing on the Gaussian disorder model and extends the pioneering work of Pasveer et al. [Phys. Rev. Lett. 94, 206601 (2005)] to higher carrier densities and large electric field. The experimental current voltage characteristics in devices based on semiconducting polymers are excellently reproduced with this model. Furthermore, we calculate and analyze some electrical properties for the relevant polymers in detail using this model.

CALCULATION AND ANALYSIS OF ELECTRICAL BEHAVIOR IN DISORDERED SEMICONDUCTING POLYMERS BASED ON EXTENDED GAUSSIAN DISORDER MODEL

We calculate and analyze some electrical properties of semiconducting polymers in detail based on the extended Gaussian disorder model.10 It is shown that the carrier density at the interface (the boundary carrier density) has an important influence on the current–voltage (J–V) characteristics. Too large or too small values of the boundary carrier density will lead to incorrect J–V characteristics. Additionally, we show that numerically calculated carrier density is a decreasing function of the distance from the interface, and the slope of curves decrease with the increasing boundary carrier density. On the other hand, numerically calculated electric field is an increasing function of the distance and the slope of curves increase with the increasing boundary carrier density. Furthermore, it is also shown that both the maximum of carrier density and the minimum of electric field appear near the interface. These results are in accordance with the experimental measurements and the simulation results.