Low-temperature magnetization and magnetoresistance of the interacting nanogranular superparamagnet Cu95 Co5

Abstract A rapidly solidified Cu 95 Co 5 alloy has been subjected to magnetization, DC susceptibility, magnetoresistance measurements in the temperature interval 5–300 K. The as-cast alloy contains a few Co nanoparticles and a large fraction of Co atoms still dispersed in the metallic matrix. Both magnetic phases are highly correlated, and undergo blocking at different temperatures. The negative magnetoresistance is mainly related to the dispersed Co phase.