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We propose a modified setup of the conventional induction method to investigate the coupling between ferromagnetic bistable wires. The idea is to prevent the saturation by an application of two additional coils near the wire ends in a conventional measurement of the hysteresis loop of the wires. In this way, the fluctuations of the switching field are eliminated. Theoretically, the system is described by phenomenological equations of motion, one equation per wire. The hysteresis loop calculated numerically agrees qualitatively with the experimental results. The comparison allows to evaluate the value of the magnetostatic coupling between the wires. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Abstract: Surface magnetization reversal has been investigated in Co-rich glass-covered microwires. Difference in mechanism of the surface magnetization reversal has been observed in the microwires with different thicknesses of glass covering. Correlation of the surface magnetic properties and the surface helical magnetic anisotropy has been found. [Copyright &y& Elsevier]

Abstract: The magnetization reversal process in Co-rich glass-covered amorphous microwires has been studied in presence of the torsion stress. The experiments have been performed using the transverse magneto-optical Kerr effect in crossed axial and circular magnetic fields. The influence of the torsion stress on the surface domain structure has been investigated. The angle of the surface helical structure has been determined based on the analysis of the stress-induced transformation of the Kerr hysteresis loops. The dependence of the angle of the helical structure on the value of the torsion stress has been obtained. [Copyright &y& Elsevier]

Abstract: The effect of torsion and tensile stress on the surface magnetic properties in Co-rich glass covered amorphous microwires has been studied. The magnetization reversal in microwires has been studied by magneto-optical Kerr effect. Calculations of hysteresis loop was performed taking into account the existence of helical magnetic anisotropy in the outer shell of the microwire. The comparative analysis of the results of the experiment and the calculation demonstrates that the observed transformation of the surface hysteresis is related to the variation of the angle of the helical surface structure. [Copyright &y& Elsevier]

We investigate a bistable amorphous iron-rich wire in AC magnetic field. Time dependence of the magnetisation M(t) is measured for the frequency of the applied field f=50 Hz. The amplitude of the applied field is chosen close to the switching field. We show that when the wire ends are free, M(t) displays oscillations twice or more longer than 1/f. We assign the effect to a magnetoelastic wave induced within the wire by the applied field. When the wire end are fixed, the effect disappears, and merely random oscillations of the switching field are observed. [Copyright &y& Elsevier]

Abstract: Magnetization reversal process has been studied in ferromagnetic amorphous wires of nominal composition Fe77.5B15Si7.5 prepared by the cold-drawing technique. Conventional hysteresis loops were measured by the fluxmetric method in the presence of the tensile stress. The measurements have been performed by short movable coils. Application of tensile stress results in increase of the remanent magnetization and decrease of the switching field. When the tensile stress is high enough, the shape of hysteresis loop is perfectly rectangular that is associated with quick enough reversals of magnetization. These hysteresis loops could be considered as quasi-magnetically bistable, but it is not exactly the standard bistability. The experiments with short movable coils have demonstrated that two domain walls (in contrast with the case of the standard bistability) propagation is responsible for the remagnetization process of the inner core. [Copyright &y& Elsevier]