Transport Properties of Active Particles Moving on Adjustable Networks

TL;DR

This paper introduces a model of active particles on adjustable networks, revealing how trail-mediated blocking influences transport properties differently from steric effects, with implications for understanding active matter dynamics.

Contribution

The study presents a minimal model of active particles on a dynamic network, highlighting the distinct impact of trail-induced blocking on particle diffusivity compared to traditional excluded-volume interactions.

Findings

Trail-mediated blocking increases diffusivity with persistence.

Steric blocking reduces diffusivity as persistence increases.

Fundamental difference in transport mechanisms identified.

Abstract

Active adaptive matter has attracted considerable interest due to its rich, largely unexplained dynamics and its relevance to a wide range of synthetic and biological materials. An important subclass of such systems consists of active particles that can remodel the network in which they move. Here, we introduce a minimal yet versatile model of active particles moving on an adjustable network. In this model, particles undergo discrete run-and-tumble motion along the links of a triangular lattice and leave behind a trail of temporarily blocked links. These closed links cannot be traversed by other particles and reopen only after a characteristic healing time. The resulting trail-mediated blocking mechanism is fundamentally distinct from more familiar interactions such as excluded-volume effects. In the high-persistence limit, we find a qualitative contrast between the two mechanisms: while steric blocking leads to reduced diffusivity with increasing persistence, trail-induced blocking causes diffusivity to increase monotonically. We characterize this fundamental difference and the associated, unexpected transport properties, and discuss potential applications of our findings.