摘要
granular magnetic Co_(x)Cu_(1-x)(x=0.05-0.5)alloy ribbons were prepared by melt spinning method,and the structural,magnetotransport,magnetic properties and the effects of annealing on these properties were studied by x-ray diffraction,vibrating sample magnetometer,magnetoresistance measurement at room temperature.Giant magnetoresistance was observed over a broad range of Co concentrations with a maximum magnetoresistance(MR)ratio of 7.8%(at x=0.20 and 500℃ annealing)under a magnetic field of 20kOe.The MR ratio increases with the annealing temperature and reaches a maximum at about 500℃ and then drops.The dependence of MR and magnetization on magnetic field for various granule parameters were studied by controlling the nucleation and growth of Co granules.
基金
Supported by the National Natural Science Foundation of China
by the State Key Laboratory of Magnet ism,Institute of Physics,Chmese Academy of Sciences.