Monte Carlo simulation of charge transport in disordered organic systems using buffer lattice at the boundary

In this paper, we present an alternative method for simulating the charge transport in disordered organic materials by using a buffer lattice at the boundary. This method does not require careful tracking of the carrier’s hopping pattern across boundaries. The suitability of this method is established by reproducing the field dependence of mobility, carrier relaxation and carrier diffusion in disordered organic systems obtained by simulating the charge transport in a lattice without implementing any boundary conditions along the electric field direction. The significance of the buffer lattice is emphasised by simulating the field dependence of mobility without using a buffer lattice, which results in negative field dependence of mobility (NFDM) at low field regime due to the extra bias the carrier gains from the neglected hops at the boundaries along the direction of the electric field.