Perpendicular magnetic anisotropy induced by antiferromagnetic Mn-Pd alloy films: Dual effects of exchange and spin-orbit coupling

Ferromagnetic (FM) films with perpendicular magnetic anisotropy (PMA) are crucial building blocks of state-of-the-art perpendicular magnetic devices. This study investigated the effects of triggering PMA in FM thin films by applying Mn1-xPdx-based antiferromagnetic (AFM) thin films with strong AFM exchange coupling from Mn and high spin-orbit coupling from Pd atoms. Our results reveal that Mn1-xPdx films can trigger PMA in Co/Ni films with weak in-plane magnetic anisotropy at room temperature through either Mn1-xPdx- facilitated interfacial perpendicular crystalline anisotropy (spin-orbit coupling, x 10%) or incorporation of them with antiferromagnet-induced exchange coupling (x 10%). In Co/Fe films with strong in-plane magnetic anisotropy, Mn-rich Mn1-xPdx films (x 10%) can induce stable PMA at low temperatures through concurrently enhanced spin-orbit coupling and antiferromagnet-induced exchange coupling across the AFM-FM interface. Our research clarifies the dual effects of exchange and spin-orbit coupling in Mn1-xPdx films, which trigger the PMA of adjacent FM films. This indicates that Mn1-xPdx films are promising candidates for achieving controllable PMA.