Systematic study of magnetization reversal in beaded fibers from different magnetic materials

Electrospun nanofibers produced from magnetic materials form a magnetic network which may be used for neuromorphic computing and other novel applications. While the influence of bending radii on the magnetization reversal in such nanofibers was already discussed in the literature, the often occurring beads along the fibers have not yet been investigated in detail. It can be assumed that such beads will support domain wall formation due to a reduction of the relative impact of the shape anisotropy, in this way influencing magnetization reversal along the fiber. Here, we simulate magnetization reversal processes in iron, nickel, cobalt and magnetite fibers with a bead in the middle, produced in three typical dimensions gained by electrospinning. In most cases a vortex state occurs during magnetization reversal, independent from the material and the dimensions. For some angular orientations of the external magnetic field, double-vortex or meander states are visible, usually also followed by vortex states. These simulations underline the strong and highly reliable impact of beads along electrospun fibers, making these structures useful for data storage, transport and other applications.