Spin reorientation at the interface of Fe/NiO(0 0 1)

Abstract

The surface spin reorientation of NiO(0 0 1) at the ferromagnetic (FM) and antiferromagnetic (AFM) interface of Fe/NiO(0 0 1) was studied by using photoemission electron microscope (PEEM) and linearly polarized X-rays. The surface spins in special domains (T 13, T 23) of bare NiO(0 0 1) are found 1.9° inclining to in-plane than the bulk spin orientation, which is explained by the surface relaxation effect. As Fe deposition, the special AFM domains observed in the PEEM images become stronger at s-polarization, while they become weaker at p-polarization. The intensity change can be explained by the in-plane canting surface spins of NiO(0 0 1) due to the exchange interaction with adjacent Fe spins. Comparing the experimental intensity ratio between the s- and p-polarization ( I s/ I p) as Fe deposition and the calculated I s/ I p as spin canting angle, the NiO(0 0 1) surface spins of the special domains are estimated inclining to in-plane about 6.0° but not in-plane completely due to the 7.5 ML Fe deposition. Moreover, the sudden drop of the intensity ratio I s/ I p suggests a spin order transition or in-plane magnetizing vibration in Fe film at around 2 ML thickness. Selecting proper incident light angles, the surface spin orientations of all the AFM domains are possible to study.