Size-dependent changeover in magnetization reversal mode of self-assembled one-dimensional chains of spherical Fe₃O₄ nanoparticles

Abstract

Understanding the ferromagnetic behavior of coupled magnetic nanoparticles (NPs) in a chain structure, called a “nanochain (NC)”, will open up new routes for its practical use. Here, we report the magnetization reversal modes in isolated magnetite (Fe3O4) NPs with diameters of 100 and 200 nm, as well as those of one-dimensional (1D) self-assembled NCs consisting of these NPs. NCs consisting of 100-nm diameter NPs switched through a transverse domain wall-like motion. Meanwhile, in 200-nm diameter NPs and NCs, we observed 3D magnetic vortex states that were more energetically favorable than single domain or multidomain states.

Unveiling the crystal and magnetic texture of iron oxide nanoflowers

“…9 The interplay between the demagnetizing field and the magnetic correlation among the cores could lead to high vorticity of the moment arrangement of the nanocrystals to minimize self-magnetic energy and consequently to the nearly zero remnant state. Interestingly, vortex-like states at zero magnetic field were found in nanocrystalline Fe 3 O 4 particles [10][11][12][13] and other magnetic nanostructures. 14 The apparent SPM behaviour makes these IONF ideal magnetic platforms for both biomedicine and water remediation purposes since the net magnetization of the IONF can be controlled at will by the application of a weak external magnetic field so that the particle agglomeration is effectively reduced.…”

“…9 The interplay between the demagnetizing field and the magnetic correlation among the cores could lead to high vorticity of the moment arrangement of the nanocrystals to minimize self-magnetic energy and consequently to the nearly zero remnant state. Interestingly, vortex-like states at zero magnetic field were found in nanocrystalline Fe 3 O 4 particles 10–13 and other magnetic nanostructures. 14…”

Crystal texture-dependent magnetic and magnetotransport properties of half-metallic Fe3O4 films grown on oxidized Si substrates by reactive deposition

“…Magnetic and transport properties of magnetite nanoparticles and thin films grown on various substrates have attracted undiverted attention of researchers over the past two decades [1][2][3][4][5][6][7][8][9]. Magnetite is a promising candidate for spintronics due to the theoretically predicted 100% spin polarization of conduction electrons [10], which is much larger than the experimentally defined values [1,4,11].…”