Controllable generation of interlayer Dzyaloshinskii-Moriya interactions in the L10-FePt/Pt/Fe multilayers for field-free magnetization switching

Abstract The interlayer Dzyaloshinskii–Moriya interaction (IL-DMI) across the non-magnetic spacer layer in a ferromagnetic/nonmagnetic/ferromagnetic metal multilayer plays a crucial role in facilitating the design of chiral spin textures and field-free magnetization switching. Until now, the induction of such IL-DMI has required either a magnetic field along the sample plane during the growth process or a wedge shape of the sample, limiting practical applicability. Here, a controllable IL-DMI induced by post-processing was generated in an L 1 0 -FePt/Pt/Fe multilayer without any special deposition conditions. However, the IL-DMI for the as-prepared sample is negligible, although an obvious difference in the magnetic anisotropy of the two ferromagnetic layers was observed by polarized neutron reflectometry measurements. When the device is applied by a large pulsed current in a tilted magnetic field, a significant IL-DMI can be generated. Meanwhile, the direction of the IL-DMI can be reversed in the L 1 0 -FePt/Pt/Fe multilayer, depending on the direction of the tilted magnetic field. Furthermore, an apparent field-free magnetization switching in the L 1 0 -FePt/Pt/Fe multilayer is achieved by the controllable IL-DMI. The experimental results reveal an interfacial effect on the IL-DMI, which paves the way for the applications of spin-logic devices based on the interlayer DMI.