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arXiv · 1409.6818

Understanding of double-curvature shaped magnetoimpedance profiles in Joule-annealed and tensioned microwires at 8-12 GHz

V. V. Popov·V. N. Berzhansky·H. V. Gomonay·F. X. Qin
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Abstract

We have investigated for the first time the combined effect of current and stress on the GMI characteristics of vanishing-magnetostrictive Co-rich microwires at microwave frequency. As the current-annealed wire is subject to certain tensile stress, one can observe a drastic transformation of field dependence of MI profiles from smooth shape of a broad peak to deformed shape of a sharp peak with the emergence of a kink on each side. It follows that three different regions- core, inner and outer shell -have been formed by the combined effect of Joule annealing, current generated magnetic field and the tensile stress. A critical field sees a drop of field sensitivity from outer to inner shell and shifts to lower value with increasing annealing current. We successfully adapted our core-shell model to a core-shell-shell model by designating different anisotropy field for each region to satisfactorily resolve the unique double-curvature shaped peaks in the field derivative MI profiles.

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V. V. Popov, V. N. Berzhansky, H. V. Gomonay, F. X. Qin. 2014-09-24. Understanding of double-curvature shaped magnetoimpedance profiles in Joule-annealed and tensioned microwires at 8-12 GHz. https://doi.org/10.1063/1.4916185

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