Hydrogenation and magnetic properties of Pd/Co multilayers

The magnetic properties of sputtered Pd/Co multilaysers in hydrogen atmospheres were studied. The x-ray diffraction(XRD) patterns in hydrogen atmospheres showed that the lattice expansion of hydrogenated Pd decreased with decreasing thickness of Pd layers, which is reminiscent of nano-crystalline Pd. Perpendicular magnetic anisotropy(PMA) and saturation magnetization were reduced by the hydrogenation. The interface anisotropy energy per unit area, Ks, and volume anisotropy energy per unit volume, Kv are discussed. These results suggest that interface magnetic anisotropy between Pd and Co layers is suppressed by hydrogenation.