Impact of Overdeposition on Magnetic Behavior in Ferromagnetic Nanowire Arrays

Owing to their dimensions and high aspect ratio, magnetic nanowires possess distinctive physical and chemical properties and are of great importance in building nanoelectronics devices. Nanowires are traditionally produced by electrochemical deposition methods using alumina or polycarbonate membranes, and their parameters (porosity, size, and arrangement of pores) strongly influence the magnetic properties of nanowires. However, very often, the effect that cannot be neglected during synthesis is overdeposition. The influence of overdeposition on the magnetic properties of nanowires is often overlooked, but it can strongly alter the magnetic behavior of the system. In this study, we use micromagnetic simulations to investigate how different levels of overdeposition affect the hysteretic behavior of nanowires and their magnetization switching mechanism. It was shown that the formation of hemispherical caps on the ends of the nanowires may alter the out-of-plane magnetic anisotropy of the nanowires and strongly influence the squareness of the hysteresis loop. The demagnetizing field distribution for nanowires with overdeposition was also investigated, showing a strong influence of its spatial distribution change on the reversal mechanism and interaction between nanowires. The obtained results were compared to existing experimental observations, showing good agreement with the magnetic behavior of the system. Performed research can be of great interest to experimental groups, as it highlights the importance of controlling overdeposition during nanowire synthesis and its potential influence on magnetic performance.