Influence of topography and Co domain walls on the magnetization reversal of the FeNi layer in FeNi/Al$\_2$O$\_3$/Co magnetic tunnel junctions

Abstract

We have studied the magnetization reversal dynamics of FeNi/Al$\_2$O$\_3$/Co magnetic tunnel junctions deposited on step-bunched Si substrates using magneto-optical Kerr effect and time-resolved x-ray photoelectron emission microscopy combined with x-ray magnetic circular dichroism (XMCD-PEEM). Different reversal mechanisms have been found depending on the substrate miscut angle. Larger terraces (smaller miscut angles) lead to a higher nucleation density and stronger domain wall pinning. The width of domain walls with respect to the size of the terraces seems to play an important role in the reversal. We used the element selectivity of XMCD-PEEM to reveal the strong influence of the stray field of domain walls in the hard magnetic layer on the magnetic switching of the soft magnetic layer.

8 Pages, 7 Figures

References in corpus (5)

• Quasi ballistic magnetization reversal
• Precessional dynamics of elemental moments in a ferromagnetic alloy
• Dynamics of magnetic domain wall motion after nucleation: Dependence on the wall energy
• Influence of domain wall interactions on nanosecond switching in magnetic tunnel junctions
• Magnetic relaxation measurements of exchange biased (Pt/Co) multilayers with perpendicular anisotropy

Cited by in corpus (1)

• Layer-resolved imaging of domain wall interactions in magnetic tunnel junction-like trilayers