This work investigates the different magnetic reversal mechanisms of as-grown and oxygen-ion (O + ) implanted Mn x O y /Ni 80 Fe 20 bilayers. A Mn x O y /Ni 80 Fe 20 bilayer was prepared by ion-beam sputter deposition in an Ar + atmosphere using a partially oxidised Mn target. Oxygen implantations were then performed using 8 keV O + ions at fluences of 10 16 , 10 17 and 10 18 ions/cm 2 to modify the exchange bias strength at the Mn x O y /Ni 80 Fe 20 interface. The magnetic, crystallographic and chemical properties of the bilayers before and after O + implantation were studied using transmission electron microscopy, X-ray reflectometry, magnetometry and polarised neutron reflectometry. The results show an overall improved exchange bias and coercivity for the O + implanted bilayers. The 10 17 ions/cm 2 implanted sample shows the greatest improvement in exchange bias and was further studied for its detailed spin-reversal behaviour using polarised neutron reflectometry. Data analysis in the magnetically-trained state reveals a coexistence of coherent rotational and non-coherent magnetic spin reversal in the as-grown sample and a solely coherent spin rotation reversal mechanism for the O + implanted Mn x O y /Ni 80 Fe 20 bilayer.
- Exchange bias
- Ion-beam implantation
- Magnetic reversal
- Polarised neutron reflectometry