Magnetic Anisotropy Evolution in CoFe/Au Barcode Nanowire Arrays

Owing to their multifunctional properties, multisegmented metallic nanowires have generated interest for potential applications in magnetics and biology. In this paper, we present the magnetic properties of Co₅₀Fe₅₀/Au barcode nanowire arrays with CoFe and Au segments of various diameters and thicknesses. The distinct anisotropic behavior and magnetization reversal process depending upon these geometric factors were investigated. As the diameter increased (50-200 nm), the easy-axis direction changed from parallel (//) to perpendicular (⊥) to the nanowire axis. As the intersegment spacing increased (t_Au = 50-200 nm), the easy-axis direction tended to lie in the plane of the nanowires. In addition, we examined the changes in the magnetization reversal modes.