Interfacial tuning of perpendicular magnetic anisotropy and spin magnetic moment in CoFe/Pd multilayers

We report on a strong perpendicular magnetic anisotropy in [CoFe 0.4 nm/Pd t]6 (t=1.0-2.0 nm) multilayers fabricated by DC sputtering in an ultrahigh vacuum chamber. Saturation magnetization, Ms, and uniaxial anisotropy, Ku, of the multilayers decrease with increasing the spacing thickness; with a Ms of 155 emu/cc and a Ku of 1.14×105 J/m3 at a spacing thickness of t=2 nm. X-ray absorption spectroscopy and X-ray magnetic circular dichroism measurements reveal that spin and orbital magnetic moments of Co and Fe in CoFe film decrease as a function of Pd thickness, indicating the major contribution of surface/interfacial magnetism to the magnetic properties of the film.