Extraordinary Hall effect in granular alloys: temperature dependence and size-effect

Summary form only given. We present the results of the theoretical study of extraordinary Hall effect (EHE) in granular alloys of the type "metal-metal" and "metal-insulator". Skew scattering is assumed to be the dominant mechanism of EHE. The calculations were carried out using the Green function technique and the effective medium approximation. The single-size electron-phonon interaction model was considered by analogy to the one in the theory of disordered alloys. It has been found that the EHE resistance of a single grain and granular alloy strongly depends on the size of grains due to the classical size-effect. The possible mechanisms of giant EHE in percolation "metal-insulator" systems are discussed.