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Induced scissoring of magnetization has been observed in aluminum/Permalloy (Ni81Fe19) thin films upon application of an alternating current. Harmonic analysis of the magnetoresistance indicates that the magnetization in the top and bottom portions of the film can rotate ±20° from the axis along which the current is applied. The opposite angles of rotation, or scissoring, can be explained by internal oersted fields from the current. These oersted fields will rotate the in-plane magnetization of the film in opposite directions through the thickness of the film. Simulation using OOMMF shows a high degree of correlation with the observed data. [ABSTRACT FROM AUTHOR]

The effect of particle size distribution on the magnetic properties of nanocrystalline [Fe.sub.86][Zr.sub.7][Cu.sub.1][B.sub.6] samples is studied in detail. The analysis applies a realistic particle size distribution, obtained from transmission electron microscopy images, to the recently developed extended Random Anisotropy Model. The effect of a broad size distribution is found to be more relevant when the tail of the distribution is larger than 20 nm. Index Terms--Nanocrystalline materials, soft magnetic materials, random anisotropy model.

On-line measurements of resistance and temperature in melt-spun [Cu.sub.90] [Co.sub.10] ribbons are made using two different annealing techniques: conventional furnace annealing, and linearly varying current Joule heating. The aim of this paper is to consider the current, flowing through the sample during the annealing, as a possible parameter to control thermal treatment parameters and thus the microstructure of these systems. Although an exact way to obtain the temperature from the annealing current remains a difficult task, the on-line changes in resistance with current allows one to identify structural changes in the sample during annealing. Also, because the temperature is found to increase continuously with electrical current, it is possible to calibrate the Joule heating system to precisely determine the annealing temperature. Index Terms--Joule heating, binary alloys, nanocrystalline materials.

We have exploited the coupling across a ruthenium spacer between a ferromagnetic and an antiferromagnetic layer to stabilize the magnetization in a given direction and tailor the magnetic sensitivity of the sensor for various applications. Ruthenium is used as the nonmagnetic coupling layer and is self-aligned with the ferromagnetic free layer and antiferromagnetic pinning layer, and the thickness is varied to change the slope of the transfer curve in the linear region, i.e., sensitivity. This simple technique is shown to increase the dynamic range of anisotropic magnetoresistive sensors without additional lithography. [ABSTRACT FROM AUTHOR]

Presents a study which reported the observation of transient spin-wave auto-oscillations in X-band pulsed subsidiary-resonance experiments in a yttrium iron garnet sphere. Methodology; Results of the study; Numerical simulations and discussion.

Discusses a study which investigated the development of granular structure in ribbons through furnace and current annealing. Materials and methodology used; Results and conclusions.

Amorphous melt-spun Fe[sub 86]Zr[sub 7]Cu[sub 1]B[sub 6] ribbons were annealed using the linear varying current Joule heating method. Experimental curves of resistance (R) and temperature (T) versus applied current (I) allow one to follow precisely the crystallization of α-Fe nanoparticles during annealing. This result proves that the applied current can be considered a reliable parameter to control the crystalline fraction in this alloy. A comparison between structural and magnetic measurements shows that the R(I) curve can be used as a guide to identify a condition for optimum soft magnetic properties of this alloy. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A potential low magnetic moment standard reference material (SRM) was studied in an interlaboratory comparison. The mean and the standard deviation of the saturation moment m s, the remanent moment m r, and the intrinsic coercivity H c of nine samples were extracted from hysteresis-loop measurements. Samples were measured by thirteen laboratories using inductive-field loopers, vibrating-sample magnetometers, alternating-gradient force magnetometers, and superconducting quantum-interference-device magnetometers. NiFe films on Si substrates had saturation moment measurements reproduced within 5 % variation among the laboratories. The results show that a good candidate for an SRM must have a highly square hysteresis loop (m r/m s > 90 %), H c ≈ 400 A·m(-1) (5 Oe), and m s ≈ 2 × 10(-7) A·m(2) (2 × 10(-4) emu).