Perfil Magnético da Multicamada MgO(001)/Fe/Ta

Abstract

In this dissertation, we build a depth magnetic profiling of the multilayer Fe(50nm)/Ta(2nm), deposited by magnetron sputtering onto the MgO(001) monocrystal substrate, by means of soft X-ray resonant magnetic reflectivity, which combines x-ray resonant reflectometry and x-ray magnetic circular dichroism. Soft Xray resonant magnetic reflectivity measurements were performed as a function of angle (setting the energy in the L2/3 absorption edge spectrum of Fe) and energy (setting the angle at approximately 10 °) at the SGM line of the Laboratório nacional de Luz Síncrotron. Results indicate that the thicknesses and densities of the layers are close to nominal values. A 70% approximate decrease was observed in the Fe magnetic moment at an 8 Å range near the Fe/Ta interface, likely due to atomic diffusion of the Ta into the Fe layer. On the other hand, a 30% increase in magnetic moment was observed near the Fe/MgO interface, possibly due to hybridization between orbital bands at the interface, though the region affected by hybridization has a relatively higher thickness than what was expected, compared to usually observed values. This discrepancy is most likely caused due to an inaccuracy of the density value determined for this sublayer, or possibly a sizable diffusion of Fe atoms into the MgO substrate might have increased the amount of Fe affected.