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Presents a study which investigated the structural and magnetic properties of (R,Zr)(Fe,Co)[sub10](R=Nd,Sm) prepared by the rapid-quenching method. Influence of the presence of zirconium; Information on the saturation magnetization of crystals; Details of the magnetic hardening of the nitrogenated materials.

Presents information on a study which investigates spin-valve structures with a magnetic material buffer layer, CoNbZr (100 Å)/NiFe (20 Å), on an oxidized silicon substrate. Measurement of the magnetoresistance ratio; Crystal structure; Experimental and calculated x-ray diffraction profile; X-ray diffraction method.

We have observed high exchange bias for a Cr2O3 film, which was crystallized from an amorphous Cr-oxide by annealing in O2 flow. To clarify the origin of the high exchange bias, we characterized the morphology of the Cr2O3 film. From X-ray diffraction, atomic force microscopy, and transmission electron microscopy measurements, we discovered that our polycrystalline Cr2O3 film was found to grow not to be entirely random orientation, but to form large R-planes on the surface. That is, R-planes were self-organized during crystallization. Since uncompensated Cr spins exist on R-planes of Cr2O3, the origin of the high exchange bias would be the self-organized R-planes. We successfully explained the peculiar temperature-dependent exchange bias and coercivity of the Cr2O3 film. For the Cr2O3 film, perpendicular exchange bias was obtained whereas out of plane direction is hard magnetization axis. This is because of the oblique Cr spin directions from out of plane direction of the film. The results demonstrated that exchange bias higher than coercivity (\mu0Hex\gg \mu0Hc) was realized near room temperature. [ABSTRACT FROM PUBLISHER]

Abstract: To confirm the origin of the exchange coupling through the nano-oxide layer (NOL), the detailed analyses of the magnetization curve and the temperature dependence on magnetization for the Co1-xFex-NOL samples with various oxidation processes are investigated. The field cooling effect is observed for NOL-inserted samples, which suggests the existence of the antiferromagnetic (AFM) component in the NOL. The characteristic temperature (blocking temperature) increases with increase in the Fe content for Co1-xFex(x=0.08,0.17,0.26)-NOL. These results support that NOL pinning appears higher than room temperature. Further, the twisted coupling through the NOL observed for the Co0.50Fe0.50-NOL is discussed from the viewpoint of the magnetic roughness due to the ferrimagnetic nature of the very thin NOL in specular spin valve (SPSV). [Copyright &y& Elsevier]