Giant magnetoimpedance in amorphous (Co0.93Fe0.7)63N10Si11B16 glass-coated microwire

Giant magnetoimpedance (GMI) effect has been measured in a glass-coated amorphous (CO0.93Fe0.7)(63)Ni10Si11B16 microwire as a function of DC magnetic field and up to the frequency of 11 MHz. The sample shows single peak GMI characteristics within the whole range of frequency. The domain structure of the above sample has been changed by applying tensile stresses up to 603 MPa and current annealing with a DC current of 50 mA for various time durations, and the corresponding effect on GMT has been studied in detail. A maximum change of 8.85% in MI of the as-quenched sample has been observed around a frequency of 5.05 MHz. Application of an external tensile stress reduces the GMT value by increasing the inner core domain, whereas heat treatment of the sample enhances the same. The square-shaped magnetic hysteresis loop of the as-quenched sample helps us understanding the MI results. (c) 2005 Elsevier B.V. All rights reserved.