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Elucidating Individual Magnetic Contributions in Bi-Magnetic Fe3 O4 /Mn3 O4 Core/Shell Nanoparticles by Polarized
I V Golosovsky1, I A Kibalin2, A Gukasov2
1National Research Center "Kurchatov Institute", B. P. Konstantinov Petersburg Nuclear Physics Institute, Gatchina, 188300, Russia.
Small Methods
|June 30, 2023
Summary
This study reveals how magnetic moments in iron oxide/manganese oxide nanoparticles reorient under varying magnetic fields. Polarized neutron diffraction precisely maps these complex interactions for advanced materials development.
Area of Science:
- Materials Science
- Nanotechnology
- Magnetism
Background:
- Heterogeneous bi-magnetic nanostructured systems exhibit unique magnetic properties and potential applications.
- Understanding the complex magnetic behavior of these systems is challenging.
Purpose of the Study:
- To comprehensively study the magnetic properties of Fe3O4/Mn3O4 core/shell nanoparticles.
- To disentangle the magnetic contributions of each component using polarized neutron powder diffraction.
Main Methods:
- Polarized neutron powder diffraction (PNPD).
- Quantitative analysis of magnetic contributions from Fe3O4 and Mn3O4 components.
- Investigation of magnetic field dependence on magnetic moments and coherence length.
Main Results:
- Fe3O4 and Mn3O4 magnetic moments are antiferromagnetically coupled at low fields and parallel at high fields.
- Mn3O4 shell moments reorient due to a field-induced evolution of magnetic susceptibility from anisotropic to isotropic.
- Unusual field dependence of Fe3O4 core magnetic coherence length observed due to competing interactions.
Conclusions:
- Polarized neutron powder diffraction is highly effective for studying complex multiphase magnetic materials.
- The study elucidates the field-dependent magnetic coupling and reorientation in Fe3O4/Mn3O4 nanoparticles.
- Findings contribute to the understanding and design of advanced magnetic nanostructures.
Keywords:
Fe3O4Mn3O4antiferromagnetic couplingcore/shell nanoparticlesmagnetic coherence lengthpolarized neutron powder diffractionMore Related Videos
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