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The effect of the ratio between the uniaxial and unidirectional anisotropy on magnetization reversal in NiFe∕MnPt bilayers has been systematically studied using vectorial vibrating magnetometer. Depending on the balance between these two anisotropies the magnetization reverses either in the opposite or the same semicircles during the ascending and descending branches of the hysteresis loop. A simple modified coherent rotation model provides a good description of the magnetization reversal in these bilayers.

Guided propagation of polarized neutrons has been observed directly in magnetic CoZr/Al/CoZr trilayer deposited on Gd 3 Ga 5 O 12 garnet substrate by using neutron reflectometry technique. The resonance observed in the transmission spectrum of neutrons corresponding to two low order guided modes is in good agreement with theoretical predictions. A detailed theoretical description of the guided propagation in thin-film neutron waveguides is also presented.

Magnetization reversal processes of Permalloy exchange coupled with thin polycrystalline antiferromagnetic multiferroic BiFeO3 films were investigated. The BiFeO3 critical thickness and the interfacial exchange energy are comparable with similar epitaxially grown systems. However, the coercive field dependence on multiferroic thickness presents an atypical behaviour. This system shows induced unidirectional, uniaxial, and biquadratic-like behaviour with misalignment of magnetic easy axis with respect to pinning field direction.