Engineering the Magnetic Anisotropy of Electrodeposited Multilayers

Induced magnetic anisotropy is important in numerous technical applications. An in-plane easy axis may be induced in an electrodeposited alloy film by deposition in an applied field. The origin of this anisotropy is thought to be preferential alignment of pairs of atoms of the same species, and the effect is generally small compared to magnetocrystalline anisotropy or surface anisotropy. Despite the phenomenon being well established, many open questions remain, including what happens to the induced anisotropy as the film thickness is reduced, or what the minimum applied field required to induce anisotropy is. We have studied the induced anisotropy in electrodeposited Fe-Co-Ni(Cu)/Cu multilayers, and find that induced anisotropy is still observed for layer thicknesses down to 2nm. We have also shown that the field required to induce anisotropy in this system is extremely low. Furthermore, it is possible to engineer the anisotropy of the film as a whole by changing the direction of the applied field during growth.