Jump to main content
Jump to site search

Issue 42, 2016
Previous Article Next Article

Anisotropic magnetic particles in a magnetic field

Author affiliations

Abstract

We characterize the structural properties of magnetic ellipsoidal hematite colloids with an aspect ratio ρ ≈ 2.3 using a combination of small-angle X-ray scattering and computer simulations. The evolution of the phase diagram with packing fraction ϕ and the strength of an applied magnetic field B is described, and the coupling between orientational order of magnetic ellipsoids and the bulk magnetic behavior of their suspension addressed. We establish quantitative structural criteria for the different phase and arrest transitions and map distinct isotropic, polarized non-nematic, and nematic phases over an extended range in the ϕB coordinates. We show that upon a rotational arrest of the ellipsoids around ϕ = 0.59, the bulk magnetic behavior of their suspension switches from superparamagnetic to ordered weakly ferromagnetic. If densely packed and arrested, these magnetic particles thus provide persisting remanent magnetization of the suspension. By exploring structural and magnetic properties together, we extend the often used colloid-atom analogy to the case of magnetic spins.

Graphical abstract: Anisotropic magnetic particles in a magnetic field

Back to tab navigation
Please wait while Download options loads

Publication details

The article was received on 20 Jun 2016, accepted on 21 Sep 2016 and first published on 22 Sep 2016


Article type: Paper
DOI: 10.1039/C6SM01411A
Citation: Soft Matter, 2016,12, 8755-8767
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    Anisotropic magnetic particles in a magnetic field

    I. Martchenko, J. J. Crassous, A. M. Mihut, E. Bialik, A. M. Hirt, C. Rufier, A. Menzel, H. Dietsch, P. Linse and P. Schurtenberger, Soft Matter, 2016, 12, 8755
    DOI: 10.1039/C6SM01411A

Search articles by author