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Fluidization Induced by Magnetic Interactions in Confined Active Matter

Marco Musacchio1,2, Markus Felber3, Matteo Paoluzzi1, Andrea Gnoli1,4, Andrea Puglisi1,4,5, and Luca Angelani1,4

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Phys. Rev. E 113, 055413 – Published 18 May, 2026

DOI: https://doi.org/10.1103/hylm-ljlf

Abstract

We investigate magnetic active matter in confined geometries using both experiments with magnetic toy robots, Hexbugs, and simulations of elongated magnetic active Brownian particles in circular domains. Standard active particles tend to accumulate at boundaries, forming clusters even at relatively low densities. In the presence of magnetic interactions, we provide evidence for a fluidization effect that inhibits clustering and shifts its onset to higher packing fractions. Moreover, magnetic dipolar interactions give rise to collective behaviors such as train-like formations, rotating pairs, and rotating clusters.

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Outline

Information

Phys. Rev. E 113, 055413– Published 18 May, 2026
  • Received 10 November 2025
  • Accepted 30 April 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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