• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.567-569
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• 1995

By using the ac field source which can change the applied field magnitude, frequency and dc offset field, the dynamic magnetoresistance characteristics of permalloy based multilayers which have different R-H(resistance-magnetic field) curves were monitored and compared with static magnetoresistance curves that were measured with electromagnet of VSM. Output of each sample according to the external field strength was identified and optimum bias position could be obtained.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.710-715
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• 1995

Magnetic domains were observed using an image lock-in technique for backscattered electron contrast (Type II) with a 200 kV scanning electron microscope. Backscattered electrons indicate a difference in magnetic domain structures at the upper and lower parts of the upper pole in thin-film heads, changing the acceleration voltage. With this method, it is also possible to observe the domain structure of the thin-film head pole through a 10 to $20\;\mu\textrm{m}$ protective layer, and the upper shield of the MR head through the coil in the resist, alumina overcoat, and upper pole.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.726-729
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• 1995

We investigated the effects of Sm on the microstructure and magnetic properties of Fe-Co Alloy films prepared by a DC triode sputtering. The magnetostriction was found to be changed with the Sm content from positive to negative values, taking a zero magnetostriction was at about 3 at% Sm. The Sm content dependence of magnetostriction was explained by the formation of Sm enriched amorphous phase surrounding the main bcc (Fe,Co) crystalline phase, which was observed by a high resolution transmission electron microscopy.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.837-840
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• 1995

Finite element analysis using two dimensional magnetic permeabillity tensor that can represents phase lag between magnetic field intensity and flux density under rotational flux is examined. Considered problem is confined to two dimensional magnetostatic case. And we applied proposed method to calculate the core loss of the test model and compare the result with that of experiment.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.351-353
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• 1995

The physical origins of anomalous volume effect (Invar effect) and elastic effect (Elinvar effect) are critically examined. We found that, unlike the volume effect, the shear elastic properties are not much influenced by the ferromagnetic transition. This finding shows that the two anomalies originate from different physical origins, thus contradicting the conventional wisdom. We discuss the consequences of this finding in the light of recent experiments.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.354-357
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• 1995

Measurements of X-ray diffuse scatterings were made in disordered single crystal of Fe-28.3 at%Pt Invar alloy around a 200-Bragg peak in a wide temperature range between 15 K and 300 K. Observed diffuse scatterings were almost spherical, suggesting a homogeneous disordered alloy. However, the qdependence of the observed thermal diffuse scattering was different from the usual type, indicating a possibility of existence of local distortion of lattice accompanied by a large gradient of stress.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.391-394
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• 1995

Simultaneous measuring system for permeability and resistivity of magnetic sheets is presented. In this system, the coil impedance is measured when a specimen is inserted between two coils. This system was applied to nickel sheets, iron-nickel alloys and a nickel film.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.408-411
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• 1995

Microstructure and magnetic properties of $Fe-Nd_{13.5}-Co_{15}-B_{6-8}Ga_{0-1}-Zr_{0.2-1}$ alloys during HDDR process were studied. $ZrB_{2}$ phase was detected and identified by X-Ray diffraction. Influence of Ga, Zr and Ga+Zr additions on phase relations at different stages of HDDR process was studied by X-ray diffraction and magnetic measurements.

• Journal of Magnetics
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• v.10 no.3
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• pp.77-79
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• 2005

In this work, we present a comprehensive and systematic approach for the derivation of the dc voltage generated by a magnetic multilayer undergoing ferromagnetic resonance, originally derived by Berger. Our alternative derivation applies especially in the limit of the spin diffusion length much longer than the carrier mean free path.

• Journal of Magnetics
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• v.10 no.3
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• pp.108-112
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• 2005

GaAs nanowires were grown on GaAs (111)B substrates in a gas source molecular beam epitaxy system, using self-assembled Au particles with diameters between 25 and 200 nm as the catalytic agents. The growth rate and structure of the nanowires were investigated for substrate temperatures between 500 and $600^{\circ}C$ to study the mass transport mechanisms that drive the growth of these crystals. The possibilities for fabrication of novel magnetic nanostructures by suitable choice of growth conditions are discussed.