COMPOSITION AND TEMPERATURE-DEPENDENCE OF GIANT MAGNETORESISTANCE IN MELT-SPUN COXCU100-X RIBBONS

Structure, magnetic properties and magnetoresistance in as-quenched an d annealed CoxCu100-x samples were investigated. Homogeneous metastabl e CoxCu100-x alloys were prepared by the single-roller technique. The maximum value of magnetoresistance is shifted to higher annealing temp eratures with increasing measuring temperature. At higher measuring te mperatures the magnetoresistance is not saturated in fields as high as 16 T. Susceptibility measurements showed the formation of hcp-structu red Co clusters. For small cobalt concentrations there is a transition from giant magnetoresistance to the normal anisotropic magnetoresista nce.