Magnetic properties of Pd/Co multilayer films studied by Hall effect

The magnetic properties and Hall effects of Pd/Co multilayer films fabricated by thermal evaporation have been studied using the Hall hysteresis loop measurement. The polarity of the Hall hysteresis loops of Pd/Co multilayer changed between 4 and 5 monolayers (ML) of Pd. It was speculated that the reason for this phenomena is the change of the position of Fermi level of 3d band in Pd/1Co multilayer from lower half of the band to upper half of the band depending on the Pd thickness. The Hall resistivities as a function of Pd thickness were found to oscillate and the period of oscillation was about 5 ML of Pd. The change of saturation magnetization as a function of Pd thickness reflected the oscillatory behavior up to 7 ML of Pd and the enhanced Co moments were observed in the film with 4 or thicker ML of Pd.