Field-responsive colloidal assemblies defined by magnetic anisotropy

Gabi Steinbach (Korresp. Autor*in), Michael Schreiber, Dennis Nissen, Manfred Albrecht, Ekaterina Novak, Pedro A. Sanchez, Sofia S. Kantorovich, Sibylle Gemming, Artur Erbe (Korresp. Autor*in)

Veröffentlichungen: Beitrag in FachzeitschriftArtikelPeer Reviewed

Abstract

Particle dispersions provide a promising tool for the engineering of functional materials that exploit self-assembly of complex structures. Dispersion made from magnetic colloidal particles is a great choice; they are biocompatible and remotely controllable among many other advantages. However, their dominating dipolar interaction typically limits structural complexity to linear arrangements. This paper shows how a magnetostatic equilibrium state with noncollinear arrangement of the magnetic moments, as reported for ferromagnetic Janus particles, enables the controlled self-organization of diverse structures in two dimensions via constant and low-frequency external magnetic fields. Branched clusters of staggered chains, compact clusters, linear chains, and dispersed single particles can be formed and interconverted reversibly in a controlled way. The structural diversity is a consequence of both the inhomogeneity and the spatial extension of the magnetization distribution inside the particles. We draw this conclusion from calculations based on a model of spheres with multiple shifted dipoles. The results demonstrate that fundamentally new possibilities for responsive magnetic materials can arise from interactions between particles with a spatially extended, anisotropic magnetization distribution.
OriginalspracheEnglisch
Aufsatznummer012608
Seitenumfang10
FachzeitschriftPhysical Review E
Jahrgang100
Ausgabenummer1
DOIs
PublikationsstatusVeröffentlicht - 18 Juli 2019

ÖFOS 2012

  • 103015 Kondensierte Materie

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