Boundary-Mediated Phases of Self-Propelled Kuramoto Particles

TL;DR

This paper explores how different microscopic driving mechanisms in self-propelled particles influence their accumulation patterns near boundaries, revealing new dynamical phases and linking microscopic interactions to macroscopic structures.

Contribution

It introduces a comprehensive analysis of boundary effects on active particles with different drives, highlighting the impact of boundary friction and providing insights into underlying microscopic interactions.

Findings

Distinct accumulation patterns depend on the microscopic drive mechanism.

Boundary friction induces new dynamical phases absent in frictionless cases.

Macroscopic structures can be linked to microscopic interactions.

Abstract

Active agents can transfer energy to their environment through collective motion, generating accumulation patterns near confining obstacles. Here we investigate how the nature of the microscopic drive-self-propulsion or velocity alignment-selects distinct accumulation patterns, leading to either delocalized or compact clustered states. We first characterize the dynamical regimes emerging from the interplay of these two driving mechanisms under perfectly reflective or smooth boundary conditions. We then introduce boundary friction and observe a drastic change in the accumulation patterns, with new dynamical phases that are absent in the previous case. By connecting emergent macroscopic structures to their underlying microscopic interactions, this work provides a practical route to infer the dominant interaction ruling boundary-mediated collective behavior, with applications ranging from single-cell migration to bio-inspired robotics.