Three-dimensional magnetic textures in iron oxide nanoflowers

Abstract

A characterization of the three-dimensional magnetization textures in iron oxide nanoflowers is presented. Tomographic reconstructions of synchrotron-based magnetic Transmission X-ray Microscopy images were obtained using precise reconstruction software, from which the texture of 34 individual particles was identified, described and categorized using geometrical and topological parameters. Four texture families were distinguished based on the morphology of the magnetization streamlines, and their robustness was tested interpreting the topological charge Q as an effective Hopf index. Furthermore, Q was established as a strong indicator of the inner magnetization structure. An apparent tendency in magnetization orientation was identified, linking the observed textures to the preferred crystalline orientations of the domains reported in previous works.