Formation of Dewetted Epitaxial Structures of Fe₃O₄/Fe and Their Magnetic Switching Properties

Herein, it is demonstrated that the solid‐state dewetting of patterned Fe(100) films can lead to the formation of epitaxial heterostructures of Fe₃O₄ and Fe. Fe₃O₄ layers can be grown conformally on multiple facets of dewetted Fe patterns, without buckle delamination, creating epitaxial interfaces. The dewetted line patterns show switching behaviors that are indicative of parallel and antiparallel coupling of Fe₃O₄ and Fe magnetization, when magnetic fields are applied along their long and short axes, respectively. By comparing this behavior with the results of micromagnetic simulations, it is suggested that the anisotropic switching behavior cannot be solely attributed to the shape anisotropy of the dewetted patterns; their interfacial atomic structures should also be considered.