The effect of Coulomb interactions on transport processes in one-dimensional systems such as discotic liquid crystals

We evaluate the consequences of interactions between charge carriers on the transport dynamics or currents in normally insulating one-dimensional syst ems where excess charges have been injected electrically, chemically, or op tically. The time-dependent currents and space charge distribution are calc ulated using a many body Monte Carlo method adapted to stochastic transport . The idea is to study collective interaction phenomena and to learn how to distinguish them from disorder effects. The latter can in principle be mod eled to explain almost any experimental result, however, this is often done at the expense of having to use unphysical or inconsistent parameters. Int eractions can we argue, give for example, rise to low frequency anomalies i n ac conductivity, negative differential resistance, low field spin magneto resistance, and critical nonlinear noise like oscillations in currents as a function of time. (C) 1999 American Institute of Physics. [S0021-9606(99)5 0320-6].