Perpendicular magnetic anisotropic characteristics of amorphous [CoSiB/Pt]N multilayers.

The perpendicular magnetic anisotropic properties of amorphous multilayers of [CoSiB/Pt]N are investigated as functions of the thickness of magnetic layers (tCoSiB = 4 and 6 Å) and the number of repeated bilayers (N = 3 ∼ 20). Even though the magnetization reversal process is dominated by the wall motion of magnetic domains rather than the nucleation for all the values of tCoSiB and N in our experiment, the changes of magnetic properties are strongly dependent on the tCoSiB and N values. The effective anisotropy constant for the 6 Å sample is K1eff = 1.2 × 106 erg/cm3, which is a factor of 6 larger than that for the 4 Å sample. The coercivity variations as a function of N are explained by the Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling between the magnetic layers considering the balance of domain wall energy and magnetostatic energy. [ABSTRACT FROM AUTHOR]