The electrical resistivity of YbBe₁₃ has been measured at high pressure up to 2 GPa and magnetic field up to 5 T. It is found that the electrical resisitivity shows a maximum near 25K (=T_max) and has -logT term in temperature range above T_max, indicating Kondo scattering of conduction electrons. The temperature of the resistivity maximum is only weakly affected by pressure but the gradients of the-logT term decrease with increasing pressure. The results is discussed in connection with the interplay between the Kondo effect and crystalline electric field.

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The hcp ordered phase of Fe₃Pt alloy thin films is for the first time successfully synthesized onto Al₂O₃ (00.1) substrates by electron beam evaporation technique. It exhibits the basal-plane 6-fold magnetic anisotropy of the order of 10⁵ erg/cc. The magnetic anisotropy varies with deposition temperature in the similar way as the intensity of hcp (00.1) superlattice peak changes. This result implies the close correlation between the basal-plane magnetic anisotropy and the occurrence of the hcp structure. The inplane magnetic anisotropy constant decreases with temperature from 2.0×10⁵ erg/cc at 80K to 1.4×10⁵ erg/cc at 300K.

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We developed a micro-fabricated cantilever with an MR sensor (MR cantilever) for use as a scanning magnetoresistance microscope (SMRM). Using a four-point MR cantilever with good signal-to-noise ratio, we have succeeded in imaging the stray field distribution of a magnetic garnet sample. Since the magnetic spatial resolution of the SMRM depends only on the physical dimensions of the MR element, the 5-μm by 1-μm MR element used in this study provided a submicronmeter spatial resolution in one direction of the SMRM.

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This paper presents a new concept for a cylindrical magnetic shield with magnetic shaking enhancement. The shield consists of two C-shaped blocks. Magnetic shaking enhancement was properly applied to the block as a result of a closed magnetic flux pass. The shape of the shield is a double concentric shell with two magnetic shunts between the outer and inner shells. The effect of the shunts on shielding performance was analyzed using an FEM program. A prototype shield model, (length: 20cm, diameter: 7.5cm, shell thickness: 0.04mm), was made by winding a cobalt-based amorphous ribbon, Metglas2705M, twice around a paper tube cut in half transversally. A large and constant transverse shielding factor of 1, 000 was obtained even against a weak low-frequency magnetic field as low as 0.1Hz, 10nT.

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The magnetic behavior of patterned Ni₈₀Fe₂₀ arrays consisting of 0.8 million nearly identical islands with a size of 1μm×5μm and 11nm thick was characterized using an alternating gradient force magnetometer and magnetic force microscopy. Magnetic hysteresis of the arrays illustrated that the average switching behavior is symmetric; however, the switching field of a single island is not symmetric. Our study clearly shows that the magnetization reversal of these islands is not coherent rotation.

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High permeability of -500 up to the GHz frequency range was observed in a CoZrNb/Fe-C multilayer film deposited by using a facing-target sputtering apparatus at room temperature. It was found that the Fe-C layer played a key role in increasing the saturation magnetization and the anisotropy field of the multilayer film sufficiently to raise the ferromagnetic resonance frequency beyond 2.0GHz. The multilayer film was soft magnetic when the thickness of the Fe-C layer was 5-50 nm. The Fe-C layer exhibited a columnar growth feature, and the aspect ratio of the column increased with increasing the Fe-C layer thickness. Magnetic anisotropy perpendicular to the film plane appeared in multilayer films with Fe-C layer thicknesses of -80nm and above.

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