The effect of spin reorientation transition of antiferromagnetic NiO on the Py magnetic anisotropy in Py/NiO/CoO/MgO(0 0 1)

Using X-ray Magnetic Linear Dichroism (XMLD) measurement, we investigate the antiferromagnetic (AFM) NiO spin reorientation transition (SRT) in epitaxial NiO/CoO/MgO(0 0 1) system at room temperature and constructed a complete NiO spin phase diagram. Then utilizing Magneto-Optic Kerr Effect (MOKE) combined with a rotation magnetic field (ROTMOKE), we investigated the effect of NiO SRT on the magnetic anisotropy of a ferromagnetic (FM) Py overlayer in Py/NiO/CoO/MgO(0 0 1) system. We find that the Py coercivity and anisotropy only slightly enhanced for Py on top of out-of-plane NiO spins but greatly enhanced for Py on top of in-plane NiO spins. Both the uniaxial and fourfold anisotropies of the Py showed a clear dependence on the NiO spin orientation.