gTASEP with Attraction Interaction on Lattices with Open Boundaries

Abstract

We study a model of aggregation and fragmentation of clusters of particles on an open segment of a single-lane road. The particles and clusters obey the stochastic discrete-time discrete-space kinetics of the Totally Asymmetric Simple Exclusion Process (TASEP) with backward ordered sequential update (dynamics), endowed with two hopping probabilities, p and pm. The second modified probability, pm, models a special kinematic interaction between the particles belonging to the same cluster. This modification is called generalized TASEP (gTASEP) since it contains as special cases TASEP with parallel update and TASEP with backward ordered sequential update for specific values of the second hopping probability pm. We focus here on exemplifying the effect of the additional attraction interaction on the system properties in the non-equilibrium steady state. We estimate various physical quantities (bulk density, density distribution, and the current) in the system and how they change with the increase of pm (p < pm<1). Within a random walk theory we consider the evolution of the gaps under different boundary conditions and present space-time plots generated by MC simulations, illustrating the applicability of the random walk theory for the study of gTASEP.