Magnetic granular CoxCuioo alloys (x - 5-20) have been prepared by melt-spinning and subsequently annealing at 450 °C for 30 min, which is most appropriate for obtaining the largest MR change with magnetic field in each sample. The highest magnetoresistance (MR) change of 42.5% was observed in annealed CoCuss ribbons. Based on the superparamagnetic assumption, the average size of Co particles embedded in a Cu-rich matrix for different samples, ranging from 3.5 to 5.5 nm, has been estimated by simulating the magnetization curves at room temperature which is higher than the blocking temperature TB for each sample. The value of MR change was found to strongly depend on the Co composition and annealing temperature.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Acoustics and Ultrasonics
- Surfaces, Coatings and Films