FIRST-PRINCIPLES THEORY OF SPONTANEOUS-RESISTANCE ANISOTROPY AND SPONTANEOUS HALL-EFFECT IN DISORDERED FERROMAGNETIC-ALLOYS

A fully relativistic first-principles theory of the conductivity of disordered magnetic alloys based on the Kubo-Greenwood formalism and the spin-polarised relativistic Korringa-Kohn-Rostoker coherent-potential approximation (SPRKKR-CPA) method is presented. This new approach allows for a treatment of spin-orbit coupling and spin polarisation on an equal footing and to account properly for the reduction in symmetry caused by the simultanous presence of them that way. Consequently-in contrast to previous approaches-one has access to a parameter-free theoretical description of the spontaneous-resistance anisotropy and the spontaneous Hall resistivity of magnetic alloys. A first application to the system Fe-Ni yields results which are in very satisfying agreement with experiment.