Magneto-impedance of glass-coated Fe-Ni-Cu microwires
arXiv:cond-mat/9911241 · doi:10.1063/1.373167
Abstract
The magneto-impedance (MI) of glass-coated Fe-Ni-Cu microwires was investigated for longitudinal radio-frequency (RF) currents up to a frequency of 200 MHz using an RF lock-in amplifier method. The MI, defined as DZ/Z = [Z(H)-Z(H=0.3T)]/Z(H=0.3T), displays a peak structure (negative MI) at zero field for RF currents with frequencies less than 20MHz and this crosses over to a sharp dip (positive MI) at higher frequencies. This crossover behavior is ascribed to the skin-depth-limited response primarily governed by the field-dependence of the permeability. Large saturation fields (300 to 600 Oe) and other anomalies indicate the possible influence of giant magneto-resistance (GMR) on the MI.
3 pages, 2-column, 3 figures. To be published in J. Appl. Phys. 2000 (44th MMM conference proceedings)