Anomalous transport in disordered exclusion processes with coupled particles

摘要

We consider one-dimensional asymmetric exclusion processes with a simpleattractive interaction, where the distance between consecutive particles is notallowed to exceed a certain limit and investigate the consequences of thiscoupling on the transport properties in the presence of random-force typedisorder by means of a phenomenological random trap picture. In thephase-separated steady state of the model defined on a finite ring, theproperties of the density profile are studied and the exponent governing thedecay of the current with the system size in the biased phase is derived. Incase all consecutive particles are coupled with each other and form a closedstring, the current is found to be enhanced compared to the model withoutcoupling, while if groups of consecutive particles form finite strings, thecurrent is reduced. The motion of a semi-infinite string entering an initiallyempty lattice is also studied. Here, the diffusion of the head of the string isfound to be anomalous, and two phases can be distinguished, which arecharacterised by different functional dependences of the diffusion exponent onthe bias. The obtained results are checked by numerical simulation.