Exchange bias‐like effect in 2D patterned thin films with perpendicular magnetic anisotropy

Abstract

Patterned magnetic materials with Perpendicular Magnetic Anisotropy (PMA) are interesting systems both, from a fundamental research point of view and also for application purposes. Usually, these systems consist in arrays of structures where the magnetic behavior is studied as a function of shape and/or structures density without changing the intrinsic magnetic properties. The use of extended films with a laterally nano/micro­‐structured magnetic property, introduce a new degree of freedom to get new building blocks that should be useful in the development of new magnetic devices. In this framework, the presented work shows how to fabricate 2D magnetically hard/soft composites by e‐beam lithography plus dry etching techniques, based on sputter‐deposited NdCo5 thin films with PMA. The laterally modulated parameter is the thin film’s thickness, which leads to the modulation of the inplane/out-­of-­plane magnetic anisotropies ratio. Due to this modulation, we are allowed to tune the magnetization reversal processes, leading to reproducible coercive field asymmetries (exchange bias­‐like effect) depending on magnetic history.