Effects of strain on magnetic anisotropy in Fe- and Co-based heterostructures

Abstract

The magnetic ordering in transition metals is strongly affected by any strain in the lattice, due to the close connection between strain and anisotropy. This article reviews recent developments, both experimental and theoretical, in the field of strain-induced magnetic anisotropies, with focus on films and multilayers based on Fe and Co. It is demonstrated that the reorientation of preferred magnetization directions can be controlled through both the growth direction and the strain state, which is caused by interleaving with suitable spacers, as well as by tuning the chemical composition if the magnetic material is an alloy. Both inplane and out-of-plane easy directions can be forced upon the films and superlattices in this manner. Some methods for local structural manipulation are also reviewed.

Spin-orbital coupling induced four-fold anisotropy distribution during spin reorientation in ultrathin Co/Pt multilayers

“…15 and 16) and Co. 4,13 In the Co ultrathin multilayers, it is because that the surface magnetic anisotropy (SMA) increases as the film thickness and temperature decreases and eventually will be strong enough to overcome demagnetizing field, aligning the magnetization to the perpendicular plane. 17 Given the weak magnetic signals of ultrathin films, only magneto-optics and ferromagnetic resonance (FMR) methods are utilized for SRT investigation. 14,18,19 Moreover, during critical SRT vicinity, the magnetic easy axis lies in intermediate state which is far from both in-plane and out-of-plane directionthe so called four-fold anisotropy distribution.…”