Giant magneto-impedance of iron whiskers

Magneto-impedance measurements on iron whiskers with 〈1 0 0〉 growth direction were performed at room temperature as a function of the applied longitudinal magnetic field and frequency of the applied current. A maximum magneto-impedance ratio of more than 60% was observed under the chosen experimental conditions. Calculations based on the standard skin effect formalism permit the determination of the complex values of the effective circumferential permeability and the skin depth. The observations on the particularly simple model system allow a very detailed analysis of the magneto-impedance contributions not having been possible for the much more complex systems studied. (paper)