Small Angle X-Ray Scattering of Neutron- and Electro-Irradiated Pd_<80>Si_<20> Amorphous Alloy

Small angle X-ray scatterig (SAXS) was measured for neutron- and electron-irradiated Pd_Si_ amorphous alloy. The experimental SAXS intensity curves are well approximated by the Guinier formula below h=0.04 A ^. The radii of gyration are almost same between electron-irradiated and aged sample, while neutron-irradiated sample shows a small radius of gyration

Gamma-ray Compton Profiles for Fe-Ti and Fe-Ti-H Amorphous Alloys

Compton profile measurements using 59.54 γ-ray source have been performed for Fe-Ti and Fe-Ti-H amorphous alloys. It is found that the electronic structure of Fe-Ti amorphous alloy is blurred by the vitrification , compared with the crystalline one , and that hydrogen atoms in Fe-Ti amorphous alloy prefer to donate valence electrons to the conduction band of the host lattice

Structure Characterization of Fe-B Amorphous Alloys by a Laboratory EXAFS Spectrometer

The local atomic arrangement for Fe-B amorphous alloys in both as-prepared and mechanically deformed states was investigated by a laboratory EXAFS spectrometer. It was found that the nearest neigh-bour distance changed drastically at 16 to 18 at% of B atom concentration and that the mechanical deformation (cold rolling and tension yielded the non-uniform displacement of Fe atoms in Fe-B amorphous alloys, keeping the Fe-B correlation unchanged

Electronic Structures of Amorphous Co-P and Ni-P Alloys by γ-ray Compton Scattering

γ-ray Compton scattering has been applied to study the electronic state of electro-deposited and melt-quenched amorphous Ni_P_ alloys, and electro-deposited amorphous Co_P_ alloy. Based on experimental Compton profiles, it is conclused that the charge transfer occurs from phosphorus atom to 3d band holes of transition metals, but 3d states may not be completely filled with electrons even in amorphous Ni_P_ alloy

The enhanced negative magnetoresistance of Fe/Tb multilayer at multiextreme conditions

金沢大学理工研究域環境デザイン学系Magnetoresistance (MR) in Fe/Tb magnetic multilayer is studied under multiextreme conditions, i.e., high magnetic field, low temperature, and high pressure. The negative MR is observed to be 24.6% in [Fe (12 nm) /Tb (15 nm)] 25 at 4.2 K, and MR is not saturated completely even up to 30 T. With increasing pressure, the magnitude of MR tends to be suppressed, indicating that magnetic order in the Tb layers is suppressed by applying pressure. © 2008 American Institute of Physics

The negative magnetoresistance of Fe/Tb magnetic multilayer

金沢大学理工研究域環境デザイン学系Magnetic twist driven magnetoresistance in Fe/Tb magnetic multilayer is studied. The negative MR ratio is observed to be 24.6 % on [Fe(12 nm)/Tb(15 nm)]25 at 4.2 K, which is much larger than that of Tb monolayer film, 9.9 %. Such large MR has never reported in multilayer systems including rare earth metal. Assuming that the MR of Tb can also be explained by the AMR effect, it means that the MR effects of the Tb layer is enhanced by spin polarization of the Fe layers. © 2009 IOP Publishing Ltd

Recent Results from LHD Experiment with Emphasis on Relation to Theory from Experimentalist’s View

he Large Helical Device (LHD) has been extending an operational regime of net-current free plasmas towardsthe fusion relevant condition with taking advantage of a net current-free heliotron concept and employing a superconducting coil system. Heating capability has exceeded 10 MW and the central ion and electron temperatureshave reached 7 and 10 keV, respectively. The maximum value of β and pulse length have been extended to 3.2% and 150 s, respectively. Many encouraging physical findings have been obtained. Topics from recent experiments, which should be emphasized from the aspect of theoretical approaches, are reviewed. Those are (1) Prominent features in the inward shifted configuration, i.e., mitigation of an ideal interchange mode in the configuration with magnetic hill, and confinement improvement due to suppression of both anomalous and neoclassical transport, (2) Demonstration ofbifurcation of radial electric field and associated formation of an internal transport barrier, and (3) Dynamics of magnetic islands and clarification of the role of separatrix