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arXiv · 2602.04732

Transport Properties of Active Particles Moving on Adjustable Networks

William G. C. Oropesa·P. de Castro·Hartmut Löwen·Danilo B. Liarte
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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.

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William G. C. Oropesa, P. de Castro, Hartmut Löwen, Danilo B. Liarte. 2026-02-04. Transport Properties of Active Particles Moving on Adjustable Networks. https://doi.org/10.1039/d6sm00135a

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