Engineering Curvature Induced Anisotropy in Thin Ferromagnetic Films

TL;DR

This paper explores how surface curvature and roughness in thin ferromagnetic films can be engineered to induce and control magnetic anisotropy, including perpendicular anisotropy, through micromagnetic energy analysis.

Contribution

It introduces a method to engineer magnetic anisotropy in thin films by manipulating surface curvature and roughness, linking surface geometry to magnetic properties.

Findings

Surface curvature can induce perpendicular anisotropy.

Periodic surface structures allow control of anisotropy direction.

Surface roughness can mimic curvature effects on anisotropy.

Abstract

The large curvature effects on micromagnetic energy of a thin ferromagnetic film with nonlocal dipolar energy are considered. We predict that the dipolar interaction and surface curvature can produce perpendicular anisotropy which can be controlled by engineering a special type of periodic surface shape structure. Similar effects can be achieved by a significant surface roughness in the film. We show that in general the anisotropy can point in an arbitrary direction depending on the surface curvature. We provide simple examples of these periodic surface structures to demonstrate how to engineer particular anisotropies in the film.