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[en] The article describes the development of spintronics from the first studies of spin dependent transport in ferromagnetic materials to the discovery of the giant magnetoresistance and to the most recent advances

[en] Published in summary form only

No abstract available

No abstract available

[en] The state-of-the-art, achievements, problems and prospects of an actively developing area of supramolecular chemistry, viz., the design of molecular ferromagnets, are considered. The bibliography includes 343 references.

[en] The electronic structure of NiMnSb is investigated by means of spin-polarized measurements of the angular correlation of annihilation radiation. NiMnSb is predicted to be a half metallic ferromagnet: the electrons of one spin direction are metallic, whereas the electrons of the opposite spin direction are semiconducting. The key question underlying this thesis was whether this is indeed true. After a general introduction the angular correlation set-up is described. The measurements are performed in a two-dimensional geometry, so that both angles in the angular correlation could be resolved. The measured distributions correspond to once-integrated two-photon momentum densities. By making use of the inherent partial polarization of the position beam and by aligning the electron-spin populations in the sample by means of an external magnetic field spin-polarized results can be obtained. After a short summary of the treatment of the (raw) angular-correlation data. The application of the Knorringa-Kohn-Rostoker (KKR) formalism to the calculation of the two-photon momentum density is discussed. To interpret the NiMnSb data, the electronic structure, the Fermi surface and the two-photon momentum densities have been obtained once integrated along three different directions inimpulse space. The difference distributions show a clear impression of the majority-spin Fermi surface. A good quantitative overall agreement between theory and experiment is established. From this analysis a value for the three-photon difference effect in NiMnSb has been obtained. To test the half-metallic nature of the band structure the experimental distributions are compared with theoretical ones obtained from modelled band structures in which small numbers of electrons near the Fermi level are transported from one spin population to the other. 167 refs.; 27 figs.; 7 tabs

[en] A phenomenological theory is elaborated on the occurrence of the parametric oscillations in a thin ferromagnetic film presenting ''a mixture'' of uniaxial and biaxial anisotropy. The study of parametric oscillation occurrence is made by means of two differential equations with periodic coefficients, among which the first describes the remagnetisation of the film by coherent rotation, and the second one the pick-up circuit. The range of this type of oscillations is found depending on the amplitude of the applied fields and the film orientation making use of the study of stability of the written system of equations. The occurrence of the oscillations is simulated on an analogical computer, remarking that the energetic transfer from the film to the pick-up circuit is made discontinuously, at time intervals depending on the magnetic properties of the film, the applied fields amplitude and the parameters of the pick-up circuit. (author)

No abstract available

[en] Published in summary form only