Ultrathin (CoFe/Pt) multilayers with tuned magnetic properties

Abstract Perpendicular magnetic anisotropy (PMA) has been investigated in ultrathin (CoFe [0.2] nm/Pt [0.2] nm) n multilayers. The Pt layers show an fcc crystal structure with a preferred [111] orientation. The multilayers with n=3, 4 show PMA in the as-grown state, which can be enhanced by thermal annealing. However, no PMA is observed in the as-grown state with higher repetitions (n>&=5), although it is observed after thermal annealing. For 1=& 5 J/m 3 for all (CoFe [0.2]/Pt [0.2]) n stacks. The perpendicular anisotropy is related to layer thickness and interface roughness.