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Abstract: A study of the influence of roughness at an antiferromagnet (AFM)/ferromagnet (FM) interface on the magnetic exchange coupling in epitaxial Co(001)/FCT-Mn(001) bilayers is presented. Co atomic monolayer thickness oscillations of the coercivity () and the exchange bias () are observed, which are clearly related to the modulated interface step density caused by the layer-by-layer growth mode of the Co(001) template films. Simulations based on a Stoner–Wohlfarth model suggest the existence of a strong intrinsic orthogonal coupling of the AFM/FM interface spins. This interaction is distinctly weakened by an increased interface roughness. [Copyright &y& Elsevier]

Abstract: We present a study of the thermal stability of tunneling spin polarization in /ferromagnet junctions based on the spin-polarized tunneling technique, in which the Zeeman-split superconducting density of states in the Al electrode is used as a detector for the spin polarization. Thermal robustness of the polarization, which is of key importance for the performance of magnetic tunnel junction devices, is demonstrated for post-deposition anneal temperatures up to 500°C with Co and Co90Fe10 top electrodes, independent of the presence of an FeMn layer on top of the ferromagnet. [Copyright &y& Elsevier]

Abstract: 59Co nuclear magnetic resonance measurements have been performed on thin epitaxial FCT-Co(001) films and the effect of an interface on the Co hyperfine field has been measured with monolayer resolution. Four different sub-lines could be measured within the bulk resonance line and were attributed to Co atoms at various distances from the interface. This effect is observable because of the virtually perfect structural quality of the Co layer, which reduces the width of the resonance lines. In less perfect systems the line width obliterates the effect. [Copyright &y& Elsevier]

Abstract: We present measurements of tunneling spin polarization (TSP) of Co72Fe20B8 alloys in Al/Al2O3/Co72Fe20B8 tunnel junctions to further unravel the role of crystallization of the CoFeB electrodes. Whereas the TSP of films of a few hundred is rather insensitive to anneals up to , a film shows a strong reduction of TSP. It is hypothesized that these differences are related to a rather inhomogeneous crystallization of the Co72Fe20B8. Magneto-optical Kerr-effect measurement on thick CoFeB wedges are used to relate the measured coercivity to these crystallization processes. [Copyright &y& Elsevier]