Angular first-order reversal curve analysis of FeNi/Cu multilayered nanowire arrays with different diameters

چکیده مقاله

magnetic performance for a variety of applications, especially three-dimensional information storage. This
stipulates the understanding of fundamental magnetic mechanisms such as magnetization reversal and switching
events in multilayer systems with tunable size. Here, a porous anodic alumina membrane-assisted electrochemical
deposition method is employed to fabricate FeNi/Cu multilayered nanowire arrays (MNWAs) with
diameters in the range of D = 35–80 nm. Angular magnetic properties of these MNWAs are investigated via
hysteresis loop and first-order reversal curve (FORC) measurements for angle fields of 0◦ ≤ θ ≤ 90◦. While the
former indicates the existence of different contributions of vortex domain wall propagation for smaller (D ≤50
nm) and larger (D >50 nm) diameters, the latter reveals the occurrence of single vortex states, depending on θ
and D. Moreover, at θ = 0◦, a transition from single domain to multidomain-like behavior appears to occur with
increasing D from 35 to 80 nm based on FORC diagrams, significantly influencing magnetization reversibility of
magnetic FeNi segments with relatively high aspect ratios (>5). The variation of magnetostatic interactions with
respect to θ is discussed and compared at each diameter as an effective factor in determining angular magnetic
properties. Also, the axial variation behavior of coercivity as a function of D is correlated with changes in the
reversible percentage, shedding light on the expectations from the vortex domain wall propagation.