Magneto-impedance effect in amorphous wires

Abstract

Recent experiments have discovered a giant magneto-impedance (MI) effect in FeCoSiB amorphous wires. This effect includes a sensitive change (as much as 60%) in a high frequency wire voltage by an applied dc magnetic field and is thus a high frequency analog of giant magnetoresistance. We consider this phenomenon in terms of ac complex resistance or impedance. The giant MI effect is demonstrated to arise from a combination of a skin effect and a strong field dependence of the circumferential magnetic permeability associated with circular domain wall movements. The theoretical results agree satisfactorily with the existing experimental data.

Development of Ultra-Thin Glass-Coated Amorphous Microwires for High Frequency Magnetic Sensors Applications

“…Circular domain structure with high circumferential permeability proved to be very favorable for the highest GMI effect [1][2]. Such domain configuration is typical for the nearly-zero magnetostrictive amorphous wires mainly produced by Japanise company Unitika LTD [1][2][3].…”

“…Such domain configuration is typical for the nearly-zero magnetostrictive amorphous wires mainly produced by Japanise company Unitika LTD [1][2][3]. On the other hand, these amorphous wires with vanishing magnetostriction constant present best magnetic softness [4].…”

“…The study of giant magneto-impedance effect (GMI) has become a topic of intensive research in the field of applied magnetism over the past years [1,2]. This GMI effect consists of a large change in the electric impedance of a magnetic conductor when the material is subjected to an axial dc magnetic field.…”

Current Annealings and Magnetoimpedance in Co-Fe Amorphous Ribbons

“…A novel magnetic phenomenon has recently received attention by both its basic and technological interests, the magnetoimpedance (MI) effect [1,2]. This phenomenon involves the impedance response of a magnetic material submitted (451) to an ac current of high frequency (1 kHz-1 MHz) and low amplitude (irms < 40 mA).…”

Very large magneto-impedance and its scaling behavior in amorphous Fe73.5Nb3Cu1Si13.5B9 ribbon

“…Interest in GMI was initiated in the early nineties when Panina et al 2 and Beach et al 6 reported a very large effect in amorphous ferromagnetic FeCoSiB wires at small magnetic fields and at relatively low frequencies. Since then, the GMI effect has been investigated in a variety of Fe-and Co-based amorphous ribbons, [7][8][9][10][11] films, [12][13][14] , wires and polycrystalline oxides [15][16][17][18][19] .…”