Continuous spin reorientation transition in epitaxial antiferromagnetic NiO thin films

Abstract

Fe/NiO/MgO/Ag(001) films were grown epitaxially and the Fe and NiO spin orientations were determined using X-ray Magnetic Dichroism. We find that the NiO spins are aligned perpendicularly to the Fe spins. Analyzing both the in-plane and out-of-plane spin components of the NiO layer, we demonstrate unambiguously that the NiO spins undergo a continuous spin reorientation transition from the in-plane to out-of-plane directions when tuning the in plane epitaxial strain from compressive to tensile with increasing the MgO thickness.

Polarized neutron powder diffraction studies of antiferromagnetic order in bulk and nanoparticle NiO

“…In thin NiO films, a spin reorientation transition, in which the orientation of the NiO spin changes from being aligned within the film to being perpendicular to the film, is observed [14,15]. This transition depends not only on the thickness of the NiO film, but also on interaction with the support and on temperature.…”

“…This transition depends not only on the thickness of the NiO film, but also on interaction with the support and on temperature. The spin orientation in thin NiO films may be influenced by epitaxial strain due to lattice mismatch between the film and its (MgO) support [14]. While there are important differences between NiO nanoparticles and thin NiO films, the two systems share the feature that a large proportion of the atoms reside on the surface and by this analogy it is interesting to investigate whether there is a spin reorientation in very thin platelet-shaped particles of NiO.…”

Exchange bias in epitaxially grown CoO/MgO/Fe/Ag(001)

“…At d MgO We would like to discuss other possible mechanisms that could affect the exchange bias. First, it is shown that the exchange bias in CoO/Fe system is not directly proportional to the CoO frozen spins [11,12]. Instead, there is a "thickness delay" between the exchange bias and the CoO frozen spins.…”

Field and temperature-driven magnetic reversal of spin-flop coupled epitaxial Fe/MnPd bilayers

“…By using x-ray magnetic dichroism, it was shown that both the unidirectional reversal characteristic and higher-order anisotropies can be present without the observation of the loop shift 8,44 .…”