Faraday effect and fragmentation of ferromagnetic layers in multilayer Co/Cu(1 1 1) nanofilms

With purpose to investigate influence of magnetically non-active metal layers on the Faraday effect in multilayer Ferromagnetic/Normal metal films, dependences of the Faraday rotation angles of the light polarization plane on magnetic field have been studied in multilayer [Co/Cu] nanofilms. It was revealed that the Faraday rotation φ varies with thickness of the Cu layers dCu. This φ(dCu) dependence consists of the monotonic component, namely a gradual rise of the angle with increase of dCu, and the non-monotonic one represented by two minima. The monotonic changes of the Faraday rotation were satisfactory described in frames of the effective medium method. Two minima are explained with the Co layer’s fragmentation due to influence of size electron quantization in the Cu layers on formation of Co clusters during deposition of the films.publishe

Giant four-fold magnetic anisotropy in nanotwinned NiMnGa epitaxial films

A giant four-fold magnetic anisotropy (with an anisotropy field up to 4 kOe) was observed in the twinned NiMnGa epitaxial film. Its appearance is explained in terms of moderate coupling between twin variants having strong uniaxial magnetocrystalline anisotropies directed orthogonally when the intertwin exchange field is comparable with the anisotropy field. This finding paves the way to increase the order of magnetic anisotropy in a many-component system while keeping the value of the anisotropy field by tuning the intercomponent exchange strength and can be extended to exchange-coupled multilayers and arrays of nanoelements