Exchange anisotropy for an ordered tetragonal PtMn/Ni80Fe 20 (110) quad-crystal film grown on an Mo(001) step surface was studied. The PtMn/Ni80Fe20 bilayers grown at 300 °C show a unidirectional exchange anisotropy with the easy axis parallel to the underlying Mo step-edge direction. The azimuthal distribution of the coercive fields displays a fourfold symmetry. The azimuthal distribution of the coercive fields can be explained by the fourfold crystalline-induced interfacial strain between Ni80Fe20 and Mo. The azimuthal distribution of the exchange fields was mainly attributed to the step-induced unidirectional anisotropy and the biquadratic coupling between antiferromagnetic-ferromagnetic interface.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering