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arXiv · cond-mat/0607366

Partially Asymmetric Exclusion Processes with Sitewise Disorder

Abstract

We study the stationary properties as well as the non-stationary dynamics of the one-dimensional partially asymmetric exclusion process with position dependent random hop rates. In a finite system of $L$ sites the stationary current, $J$, is determined by the largest barrier and the corresponding waiting time, $τ\sim J^{-1}$, is related to the waiting time of a single random walker, $τ_{rw}$, as $τ\sim τ_{rw}^{1/2}$. The current is found to vanish as: $J \sim L^{-z/2}$, where $z$ is the dynamical exponent of the biased single particle Sinai walk. Typical stationary states are phase separated: At the largest barrier almost all particles queue at one side and almost all holes are at the other side. The high-density (low-density) region, is divided into $\sim L^{1/2}$ connected parts of particles (holes) which are separated by islands of holes (particles) located at the subleading barriers (valleys). We also study non-stationary processes of the system, like coarsening and invasion. Finally we discuss some related models, where particles of larger size or multiple occupation of lattice sites is considered.

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BibTeXRIS

Róbert Juhász, Ludger Santen, Ferenc Iglói. 2006-07-14. Partially Asymmetric Exclusion Processes with Sitewise Disorder. https://doi.org/10.1103/physreve.74.061101

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