Effects of the antiferromagnetic spin structure on antiferromagnetically induced perpendicular magnetic anisotropy

Antiferromagnetic (AFM) thin films are promising materials for inducing perpendicular magnetic anisotropy (PMA) in adjacent ferromagnetic (FM) films. This study demonstrates that in a selected AFM spin structure with out-of-plane uncompensated moments, the magnitude of the induced PMA in its neighboring Co/Ni film could be significantly enhanced by the establishment of a collinearlike exchange interaction between the volume moments of the AFM film and the perpendicular magnetic FM film. Detailed magnetic hysteresis loops and x-ray analysis revealed a quench of perpendicular surface anisotropy in a monolayered ${\mathrm{Fe}}_{50}{\mathrm{Mn}}_{50}/\mathrm{Co}/\mathrm{Ni}$ film due to the formation of antiparallel-like coupled Fe and Mn moments. By contrast, the establishment of a three-dimensional quadratic-type AFM spin structure of an ${\mathrm{Fe}}_{50}{\mathrm{Mn}}_{50}$ film triggered parallel-like out-of-plane uncompensated Fe and Mn moments at the interface and reinforced the PMA induced in the Co/Ni film.