Interlayer exchange coupling in Ni/Al/Py heterostructures

Abstract

This study investigates the magnetic behavior of Py/Al/Ni heterostructures to evaluate the effect of the Al spacer thickness on the interlayer coupling. Hysteresis loops for sample series with 5 nm and 10 nm Py layers were measured using Magneto-Optic Kerr Effect (MOKE). The results indicate that the direct contact samples appear to be strongly coupled and switch collectively. The introduction of Al attenuates this interaction, enabling the observation of independent switching and stable antiparallel states in specific configurations. Furthermore, the increase of Py thickness has been seen to modify the interlayer coupling. However, the intrinsic magnetic anisotropy of the Py layer complicates this characterization by masking the underlying magnetic behavior. Our results highlight the importance of structural control for the development of magnetic memories such as MRAM.