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Dissipative self-assembly of colloidal suspensions

Jason Conradt and Eric M. Furst*

  • Department of Chemical and Biomolecular Engineering, Allan P. Colburn Laboratory, 150 Academy St., University of Delaware, Newark, Delaware 19716, USA

  • *Contact author: furst@udel.edu
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Phys. Rev. E 114, 025416 – Published 21 August, 2026

DOI: https://doi.org/10.1103/8h2w-vhcn

Abstract

Suspensions of paramagnetic colloids exhibit kinetic arrest in strong magnetic fields. Through a dissipative process of toggling the field on and off, suspensions self-assemble into dense and dynamic steady-state phases. We construct a phase diagram using k-means clustering analysis based on domain elongation, α-shapes, contour metrics, and the degree of phase separation. We identify six characteristic structural regimes: a structureless phase, an arrested structure, sheets, ribbons, a spiky phase, and a transient fluid-fluid regime. We further report the distribution and alignment of domains and the generality of the results. We model self-assembled domain shapes using an equilibrium mean-field magnetostatic energy calculation, which predicts the surprising emergence of highly anisotropic structures driven by the sample's confinement.

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Phys. Rev. E 114, 025416– Published 21 August, 2026
  • Received 31 March 2026
  • Accepted 6 July 2026
Article part of CHORUS
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