Modelling space-charge limited transport in discotic liquid crystals

Using a self-consistent Monte Carlo/Poisson algorithm, we investigate space-charge limited conduction in discotic liquid crystal time of flight (TOF) experiments. The charge transport mechanism is via a semi-delocalised banding process, and two mechanisms of photo-generation of charge carriers are considered: excitons generated by the laser pulse, which quench at the anode, and processes, such as the Onsager mechanism, that lead to direct generation of free electron/hole pairs within the bulk. The nature of the space-charge limited TOF transient is investigated as a function of quantum yield of charge carriers and as a function of applied potential.