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Magneto-impedance (MI) effects have been observed in amorphous and nanocrystalline Fe73.5CuNb3Si13.5B9 ribbons. Large MI values have been obtained in nanocrystalline samples (NCS), but not in as-quenched samples (AQS). The magnetic responses of impedance of nanocrystalline samples share some common features with that of Co-based amorphous wire and ribbon samples. The field dependencies of effective permeability for nanocrystalline samples have shown a sharp change at the anisotropy field. The effective permeability and the hysteresis loops for AQS and NCS have been shown to be responsible for their MI effects. The sensitivity of the magnetic responses in the nanocrystalline sample can reach 50%/Oe.

Formations of endohedral complexes in collisions of H2 and D2 with C60 molecules have been studied using a molecular dynamics simulation method. H@C60 complex is produced when a H2 molecule collides with a C60 molecule along the direction from the center of a hexagonal ring into the center of the C60 at collision energy E0 = 40 eV. At the same collision condition, a D2 molecule colliding with a C60 molecule forms a D2@C60 complex.

The low Gilbert damping factor, which is usually measured by ferromagnetic resonance, is crucial in spintronic applications. Two-magnon scattering occurs when the orthogonality of the ferromagnetic resonance mode and other degenerate spin wave modes was broken by magnetic anisotropy, voids, second phase, surface defects, etc., which is important in analysis of ferromagnetic resonance linewidth. Direct fitting to linewidth with Gilbert damping is advisable only when the measured linewidth is a linear function of measuring frequency in a broad band measurement. We observe the nonlinear ferromagnetic resonance linewidth of Co2MnSi thin films with respect to measuring frequency in broad band measurement. Experimental data could be well fitted with the model including two-magnon scattering with no fixed parameters. The fitting results show that two-magnon scattering results in the nonlinear linewidth behavior, and the Gilbert damping factor is much smaller than reported ones, indicating that our Co2MnSi films are more suitable for the applications of spin transfer torque.

granular magnetic CoxCu1-x (x = 0.05 - 0.5) alloy ribbons were prepared by melt spinning method, and the structural, magnetotransport, magnetic properties and the effects of annealing on these properties were studied by x-ray diffraction, vibrating sample magnetometer, magnetoresistance measurement at room temperature. Giant magnetoresistance was observed over a broad range of Co concentrations with a maximum magnetoresistance (MR) ratio of 7.8% (at x = 0.20 and 500°C annealing) under a magnetic field of 20 kOe. The MR ratio increases with the annealing temperature and reaches a maximum at about 500°C and then drops. The dependence of MR and magnetization on magnetic field for various granule parameters were studied by controlling the nucleation and growth of Co granules.

Giant magneto-impedance effects have been observed in as-deposited amorphous FeCuNbSiB/Cu/FeCuNbSiB and FeCuNbSiB/SiO2/Ag/SiO2/FeCuNbSiB multilayered films. The films were deposited onto Si substrates by radio frequency sputtering. In FeCuNbSiB/Cu/FeCuNbSiB films, maximum giant magneto-impedance ratios as large as 32% and 11% were obtained at 13 MHz in the longitudinal and transverse fields, respectively. In FeCuNbSiB/SiO2/Ag/SiO2/ FeCuNbSiB films, the maximum giant magneto-impedance ratios were 47% and 57% at the same frequency for the two cases, which are much larger than those obtained in the annealed single layer films.

Co2MnSi thin films are made by magnetron sputtering onto MgO (001) substrates. The crystalline quality is improved by increasing depositing temperature and/or annealing temperature. The sample deposited at 550°C and subsequently annealed at 550°C (sample I) exhibits a pseudo-epitaxial growth with partially ordered L21 phase. Sample I shows a four-fold magnetic anisotropy, in addition to a relatively weak uniaxial anisotropy. The Gilbert damping factor of sample I is smaller than 0.001, much smaller than reported ones. The possible reasons responsible for the small Gilbert damping factor are discussed, including weak spin-orbit coupling, small density of states at Fermi level, and so on.

Impulse-copling coefficients, for A1 and Cu samples with finite surface area irradiated in air by 1.06 μm, 10 ns laser pulses produced by a Nd: YAG laser, have been measured experimentally. A modified theoretical model of impulse-coupling is proposed, which significantly improves the agreement between the calculated impulse-coupling coefficient and the measured one.

FexGe1?x/Ge amorphous heterojunction diodes with p-FexGe1?x ferromagnetic semiconductor layers are grown on single-crystal Ge substrates of p-type, n-type and intrinsic semiconductors, respectively. The I?V curves of p-Fe0.4Ge0.6/p-Ge diodes only show slight changes with temperature or with magnetic field. For the p-Fe0.4Ge0.6/n-Ge diode, good rectification is maintained at room temperature. More interestingly, the I?V curve of the p-Fe0.4Ge0.6/i-Ge diode can be tuned by the magnetic field, indicating a large positive magnetoresistance. The resistances of the junctions decrease with the increasing temperature, suggesting a typical semiconductor transport behavior. The origin of the positive magnetoresistance is discussed based on the effect of the electric and magnetic field on the energy band structures of the interface.

Intrinsic charge transfer in mixed halide compounds PtXxX'1-x was studied in the framework of the two-band extended Pielerls-Hubbard model. It was found that the number of transferred charges can be a fraction times of the electronic charge. The maximum amount of the transferred charges will occur at a certain proportion x for a given mixed compound.

The paramagnetic parameters of the Nd2Fe14B single crystal were measured. In the temperature range from about 600K to 830K, the temperature dependence of the reciprocal susceptibility obeyed Curie-Weiss law, from which the effective magnetic moment for Fe atoms, 3.97μB/Fe atom, can be obtained.