Perpendicular magnetization behaviors of Co/FeMn/Co multilayers with and without Pt spacer

Abstract

The interfacial effect on the magnetization in the magnetron sputtered Co/FeMn/Co multilayers with Pt spacer layer upon and beneath the FeMn layer, respectively, was investigated. The variation in the magnetization with the thickness of the Co layer strongly depends on the orientation and the rotation of the interfacial spins at the ultrathin limit of the Co layer as well as the FeMn layer, which is determined by the magnetic anisotropy at the ferromagnetic/antiferromagnetic interface. The perpendicular magnetization is considerably enhanced by the FeMn layer either with or without the Pt spacer, and the enhancement is cut down by inserting the Pt spacer at the Co/FeMn interface, whereas nearly not changed by the Pt spacer at the FeMn/Co interface. Although a perpendicular inducing field is applied during the deposition, the perpendicular exchange bias is not induced at the Co/FeMn interface unless a 0.4 nm Pt spacer is inserted, indicating that the interfacial uncompensated spins could hardly be pinned into the hard axis. © 2010 American Institute of Physics.