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Title: Giant magnetoimpedance sensor integrated in an oscillator system

Abstract

This article presents a magnetic field measurement system using giant magnetoimpedance (GMI) sensor as a phase shift element. Investigations were carried out using CoFeB trilayer thin films with 2 kA/m anisotropy field structured as strips and meanders of 300 {mu}m length presented in previous studies. The GMI sensor is integrated into an oscillator circuit. The measurement system detects the phase change caused by the magnetic field to be measured. A 6.85% impedance decrease at an applied field of 1.4 mT was observed. The phase difference in such cases was {delta}{phi}=1.12 deg. . The transmission constant was {mu}{sub a}/{delta}{phi}=1 mV/deg.

Authors:
; ; ;  [1]
  1. Institute of Sensor and Actuator Systems, Vienna University of Technology, Gusshausstrasse 25-29/366, Vienna, A-1040 (Austria)
Publication Date:
OSTI Identifier:
20788118
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 8; Other Information: DOI: 10.1063/1.2170051; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; BORON ALLOYS; COBALT ALLOYS; IMPEDANCE; IRON ALLOYS; MAGNETIC FIELDS; MAGNETORESISTANCE; OSCILLATORS; PHASE SHIFT; THIN FILMS

Citation Formats

Giouroudi, I., Hauser, H., Musiejovsky, L., and Steurer, J. Giant magnetoimpedance sensor integrated in an oscillator system. United States: N. p., 2006. Web. doi:10.1063/1.2170051.
Giouroudi, I., Hauser, H., Musiejovsky, L., & Steurer, J. Giant magnetoimpedance sensor integrated in an oscillator system. United States. doi:10.1063/1.2170051.
Giouroudi, I., Hauser, H., Musiejovsky, L., and Steurer, J. Sat . "Giant magnetoimpedance sensor integrated in an oscillator system". United States. doi:10.1063/1.2170051.
@article{osti_20788118,
title = {Giant magnetoimpedance sensor integrated in an oscillator system},
author = {Giouroudi, I. and Hauser, H. and Musiejovsky, L. and Steurer, J.},
abstractNote = {This article presents a magnetic field measurement system using giant magnetoimpedance (GMI) sensor as a phase shift element. Investigations were carried out using CoFeB trilayer thin films with 2 kA/m anisotropy field structured as strips and meanders of 300 {mu}m length presented in previous studies. The GMI sensor is integrated into an oscillator circuit. The measurement system detects the phase change caused by the magnetic field to be measured. A 6.85% impedance decrease at an applied field of 1.4 mT was observed. The phase difference in such cases was {delta}{phi}=1.12 deg. . The transmission constant was {mu}{sub a}/{delta}{phi}=1 mV/deg.},
doi = {10.1063/1.2170051},
journal = {Journal of Applied Physics},
number = 8,
volume = 99,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
  • Fe{sub 73-x}Al{sub x}Si{sub 14}B{sub 8.5}Cu{sub 1}Nb{sub 3.5} (x=0,2) nanocomposite materials consisting of a nanocrystalline phase in an amorphous matrix were obtained by annealing their precursor amorphous ribbons, which were prepared by the melt-spinning technique, at different temperatures ranging between 350 and 650 deg. C for 45 min in vacuum. Investigation on their magnetic and magnetoimpedance properties indicates that the Al-containing sample (x=2) possesses superior magnetic softness and giant magnetoimpedance (GMI) effect over the Al-free counterpart. This can be likely ascribed to the increased magnetic permeability, decreased coercive force, and decreased resistivity. The increased magnetic permeability results from a reduction inmore » magnetocrystalline anisotropy and saturation magnetostriction. The correlations between magnetic softness, electrical properties, and GMI behavior are discussed in the light of the skin effect model. These results indicate that the Al-containing Fe-based nanocomposite material can be ideally used for high-performance GMI sensor applications.« less
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  • The magnetic permeability and giant magnetoimpedance effect of Fe{sub 73.5}Cu{sub 1}Mo{sub 3}Si{sub 13.5}B{sub 9} alloy ribbons in different annealed states have been measured as functions of the external magnetic field and the ac driving current frequency. It is found that the giant magnetoimpedance effect in the magnetic-field annealed state is larger than that in the nonfield annealed state. In the field annealed state, the easy magnetization direction is along the driving current as well as the external magnetic field. This leads to significant change of the permeability at high frequencies, and consequently the magnetoimpedance is enhanced in this state. {copyright}more » {ital 1997 American Institute of Physics.}« less
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