Two-species TASEP model: from a simple description to intermittency and travelling traffic jams

TL;DR

This paper extends the TASEP model to two species with different entry and exit rates, providing a mean-field analysis, phase diagram, and insights into intermittency and traffic jams through simulations and refined theory.

Contribution

It introduces a two-species TASEP model with a comprehensive mean-field analysis and a refined intermittent mean-field theory to explain deviations observed in simulations.

Findings

Mean-field phase diagram for two-species TASEP

Confirmation of theoretical predictions via stochastic simulations

Identification of intermittency as a key factor in deviations

Abstract

We extend the paradigmatic and versatile TASEP (Totally Asymmetric Simple Exclusion Process) for stochastic 1d transport to allow for two different particle species, each having specific entry and exit rates. We offer a complete mean-field analysis, including a phase diagram, by mapping this model onto an effective one-species TASEP. Stochastic simulations confirm the results, but indicate deviations when the particle species have very different exit rates. We illustrate that this is due to a phenomenon of intermittency, and formulate a refined 'intermittent' mean-field (iMF) theory for this regime. We discuss how non-stationary effects may further enrich the phenomenology.