Novel Phases and Finite-Size Scaling in Two-Species Asymmetric Diffusive Processes

TL;DR

This paper investigates phase transitions and finite-size effects in a two-species asymmetric diffusive lattice gas, combining mean-field theory with simulations to reveal complex behaviors and scaling properties.

Contribution

It introduces a mean-field framework connecting microscopic dynamics to macroscopic phases in a two-species asymmetric diffusion model, with detailed finite-size scaling predictions.

Findings

Identification of phase transitions between uniform and non-uniform states.

Excellent agreement between theory and simulations for density profiles.

Discovery of large-size scaling behavior similar to self-organized sandpile models.

Abstract

We study a stochastic lattice gas of particles undergoing asymmetric diffusion in two dimensions. Transitions between a low-density uniform phase and high-density non-uniform phases characterized by localized or extended structure are found. We develop a mean-field theory which relates coarse-grained parameters to microscopic ones. Detailed predictions for finite-size ($L$) scaling and density profiles agree excellently with simulations. Unusual large-$L$ behavior of the transition point parallel to that of self-organized sandpile models is found.