Characteristics of the asymmetric simple exclusion process in the presence of quenched spatial disorder

We investigate the effect of quenched spatial disordered hopping rates on the characteristics of the asymmetric simple exclusion process (ASEP) with open boundaries both numerically and by extensive simulations. Disorder averages of the bulk density and current are obtained in terms of various input and output rates. We study the binary and uniform distributions of disorder. It is verified that the effect of spatial inhomogeneity is generically to enlarge the size of the maximal current phase. This is in accordance with the mean field results obtained by Harris and Stinchcombe. Furthermore, we obtain the dependence of the current and the bulk density on the characteristics of the disorder distribution function. It is shown that the impact of disorder crucially depends on the particle input and out rates. In some situations, disorder can constructively enhance the current.