Mapping the transition from quasi-2D to 3D spin textures in NiFe nanomagnets

Abstract

With increasing interest in understanding and mapping the spin textures within magnetic nanostructures, this work reports a study of the transition from quasi-2D magnetic behavior in thin-film ferromagnetic nanostructures to 3D thick-film nanostructures. A series of arrays of 480 × 250 nm2 elliptical Ni81Fe19 nanomagnets patterned using deep ultraviolet (DUV) lithography with thickness (t) ranging from 20 to 250 nm were studied. It is shown through magnetometry and micromagnetics that as the film thickness increases, the nanomagnets transition from effectively planar 2D magnets, with uniform spin textures extending through the film thickness for t ≤ 50 nm, to 3D nanomagnets with more complex non-uniform 3D spin textures for t ≥ 100 nm. These results demonstrate that the fabrication of thick-film nanomagnets via DUV lithography is a viable route to producing consistent 3D magnetic nanostructures for potential applications, such as magnonics.