Disordering, Clustering, and Laning Transitions in Particle Systems with Dispersion in the Magnus Term

TL;DR

This study numerically explores how particles with different Magnus terms undergo disordering, phase separation, and laning transitions under drive, revealing complex behaviors relevant to skyrmion systems.

Contribution

It introduces the first detailed numerical analysis of disordering and laning transitions in particle systems with Magnus term disparity under drive.

Findings

Magnus-induced disordering transition occurs at a critical drive due to Hall angle differences.

Disordered states can phase separate into density-modulated stripes perpendicular to drive.

Multiple phases, including laned and pattern-forming states, emerge as functions of drive and Magnus disparity.

Abstract

We numerically examine a two-dimensional system of repulsively interacting particles with dynamics that are governed by both a damping term and a Magnus term. The magnitude of the Magnus term has one value for half of the particles and a different value for the other half of the particles. In the absence of a driving force, the particles form a triangular lattice, while when a driving force is applied, we find that there is a critical drive above which a Magnus-induced disordering transition can occur even if the difference in the Magnus term between the two particle species is as small as one percent. The transition arises due to the different Hall angles of the two species, which causes their motion to decouple at the critical drive. At higher drives, the disordered state can undergo both species and density phase separation into a density modulated stripe that is oriented perpendicular to the driving direction. We observe several additional phases that occur as a function of drive and Magnus force disparity, including a variety of density modulated diagonal laned phases. In general we find a much richer variety of states compared to systems of oppositely driven overdamped Yukawa particles. We discuss the implications of our work for skyrmion systems, where we predict that even for small skyrmion dispersities, a drive-induced disordering transition can occur along with clustering phases and pattern forming states.