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We study the nonlocal spin and charge current generation in a finite metallic element on the surface of magnetic insulators such as yttrium iron garnet due to the absorption of the magnetic surface plasmon (MSP). Whereas a surface plasmon is completely reflected by a metal, an MSP can be absorbed due to the absence of backward states. The injection of MSP generates a voltage in the longitudinal direction parallel to the wave vector, with the voltage proportional to input power. If the metal is a ferromagnet, a spin current can also be induced in the longitudinal direction. Our results provide a way to improve upon integrated circuits of spintronics and spin wave logic devices. [ABSTRACT FROM AUTHOR]

A molecular dynamic model of the properties of a strongly interacting particulate dispersion is described. The particles concerned are assumed to be acicular and the model is applied to the study of the properties of a dispersion of advanced metal particles for recording media. The model is applied to predictions of the magnetic behaviour of dispersions under shear, providing a basis for the understanding of shear magnetometry. The hydrodynamics of the dispersion are shown to be important as regards the microstructure of the final coated recording medium.

Temperature-dependent resistivity, thermoelectric power, and magnetoresistance (MR) are investigated in YBa2Cu3O7/La0.7Sr0.3MnO3 (YBCO/LSMO) bilayers with the thickness of YBCO fixed at 150 nm and that of LSMO varying from t=0 to 50 nm. It is found that the onset temperature Tc of the superconducting transition retains at a constant value of 74 K for t<50 nm, but reduces to 20 K at t=50 nm. In conjunction with the existence of a critical thickness of 50 nm for delocalizing charge carriers in the LSMO layer, we attribute the Tc suppression to the diffusion of spin-polarized carriers from the metallic LSMO to the YBCO layer. Furthermore, we observe a sign reversal of MR with temperature in the YBCO(150 nm)/LSMO(50 nm) bilayer, indicating a competition between a positive MR of YBCO and a negative MR of LSMO. [ABSTRACT FROM AUTHOR]

A magnetic tunnel junction (MTJ) with orthogonal magnetic anisotropy and consisting of Ta X/Co40Fe40B20 1.2 (reference)/MgO 2.0/Co20Fe60B20 2.3 (sensing)/Ta 5/Ru 5 (thickness in nanometers), where X ranges from 15 to 30, is proposed and investigated in response to the demand for out-of-plane field sensors. The reference layer with perpendicular magnetic anisotropy (PMA) demonstrates tuneable coercivity ranging from 72 Oe to 175 Oe. The sensing layer exhibits in-plane anisotropy with the avoidance of exchange coupling from the PMA reference layer because of a thick MgO barrier layer. The magnetization reversal behavior of micron scale devices not only corresponds well to the sheet film, but is also independent in terms of shape and size. The magnetoresistance curve exhibits a ratio of ~27% in the presence of a perpendicular field and is insensitive to the in-plane field. For perpendicular field sensing, the dynamic range with a sensitivity of ~0.3%/Oe can achieve ±25 Oe with a coercive field of less than 3 Oe. Additionally, even when bias is applied up to 9.1 mV, magnetic fluctuation still stays below 0.15 mOe. [ABSTRACT FROM AUTHOR]

Describes a disk model developed to simulate the propagation of a cylindrical relativistic electron beam through plasma into vacuum. Details of electron and ion flow shown by simulation results; Information on the high-energy tail in the ion distribution; Comparison with a one-dimensional sheet model.

Pure spin transport via spin pumping in the condition of ferromagnetic resonance can be transformed to charge current in the ferromagnetic/paramagnetic bilayer systems, based on inverse spin Hall effect (ISHE). Here, we explore La0.7Sr0.3MnO(x)/Pt(5.5 nm) [x = 10 to 65 nm] bilayers to investigate the influence of damping constant on spin pumping efficiency. The results show that the ISHE voltage depend on the damping constant of magnetic moment, suggesting that the precession energy tansferred to lattice/electron of normal metal is a key parameter to control the magnitude of spin current. [ABSTRACT FROM AUTHOR]

Field evolution of vortex and cross-tie states is investigated by magnetic force microscopy imaging experimentally. We found that the vortices move perpendicular to the field direction. For the multivortex states, as the external field is perpendicular to the magnetization direction of the rhombic domain, which is enclosed by two neighboring vortices, the rhombic domain tilts. When the external field is parallel/antiparallel to the magnetization direction of the rhombic domain, this domain is extended/contracted. For the cross-tie state, the vortex and antivortex cores annihilate pair by pair in series when the field is applied along the short axis. When the magnetic field is applied along the long axis, the Bloch line moves along the short-axis direction till it, as a whole, annihilates near the edge of the elliptical thin film. [ABSTRACT FROM AUTHOR]

A microstructured permalloy ellipse with six equally spaced nonmagnetic voltage leads has been studied through magnetoresistance measurements and magnetic force microscopy. The aspect ratio and film thickness of the element having three vortices of magnetic configuration were accordingly designed and fabricated using electron-beam lithography through a lift off process. Magnetoresistance curves measured with various pairs of voltage leads have revealed a local magnetic-moment reversal. Two magnetoresistance kinks observed with decreasing/increasing field strength can be attributed to the vortex formation/annihilation, which was confirmed by magnetic force microscopy and micromagnetic simulation. The motion of the vortex core driven by the transverse external magnetic field was estimated to be 4.1 nm/Oe. [ABSTRACT FROM AUTHOR]

Pure phase of [Co3(pyz)(HPO4)2F2] crystal powder was successfully synthesized. The structure consisted of neutral sheets of [Co3(HPO4)2F2], which were pillared through pyrazine ligand to form three-dimensional frameworks. Below 20 K, the magnetic hysteresis loops showed a ferromagnetic part superimposed with an antiferromagnetic (AF) part. With increasing field magnitude, the AF part showed sharp steps at 5 kOe. Micromagnetic simulation, taking into account the Co ions as AF coupled sublattices and as suggested by the negative Weiss temperature extrapolated by the inverse susceptibility versus temperature behavior, explained the hysteresis loops the temperature dependence qualitatively. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Pure phase of [Co3(pyz)(HPO4)2F2] crystal powder was successfully synthesized. The structure consisted of neutral sheets of [Co3(HPO4)2F2], which were pillared through pyrazine ligand to form three-dimensional frameworks. Below 20 K, the magnetic hysteresis loops showed a ferromagnetic part superimposed with an antiferromagnetic (AF) part. With increasing field magnitude, the AF part showed sharp steps at 5 kOe. Micromagnetic simulation, taking into account the Co ions as AF coupled sublattices and as suggested by the negative Weiss temperature extrapolated by the inverse susceptibility versus temperature behavior, explained the hysteresis loops the temperature dependence qualitatively. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Micron size NiFe wire having a patterned shape of semicircle in series was fabricated. Magnetoresistance of the wire has been studied from 10 to 300 K. Domain wall resistivity is nearly independent of the temperature; however, the domain wall switching field decreases relatively rapidly with increasing temperature. We have observed experimentally two distinct domain structures at the corners of the NiFe semicircle-ring patterned wire at remanence after longitudinal and transverse saturation fields. We can explain successfully the magnetization reversal process on the magnetoresistance loops by the contribution from anisotropic magnetoresistance and magnetic domain configuration. [ABSTRACT FROM AUTHOR]

Through the proper design of submicron permalloy (Ni[SUB80]Fe[SUB20]) wires, domain wall magnetoresistance is investigated. A positive contribution to magnetoresistance (MR) was found for domain walls in these wires after extracting the anisotropic MR effect. Some theoretical models are used to discuss our results. [ABSTRACT FROM AUTHOR]

Presents information on a study which proposed a model which links electron beam propagation through plasma into a vacuum with collective ion acceleration from the plasma. Configuration of an electron beam propagation through a plasma region into a vacuum drift tube; Derivation of a momentum-balance equation.

Presents a study that examined a bicrystal film. Comparison between deposited bicrystal film and deposited film of uniaxial clusters; Information on the properties of the films; Discussion on the role of bicrystal films in material science and their applications to information storage.

Presents an equation for the damped dynamics of magnetization in ferromagnets. Information on a ferromagnet mathematical model with uniaxial anisotropy; Discussion on the relaxation of the modulus of magnetization; Derivation of the equation for the damped dynamics of magnetization in ferromagnets.

La0.7Sr0.3MnO3(LSMO) and Pt capped La0.7Sr0.3MnO3 20 nm thick films have been grown on SrTiO3 substrates by pulsed laser deposition. Microstrip line ferromagnetic resonance (MS-FMR) technique is then used to investigate their magnetic dynamic properties and to particularly measure the damping constant based on the frequency dependence of microwave absorption linewidth. The results show that the effective damping constant of LSMO(20nm)/Pt(5.5nm) is three times larger than that of LSMO(20nm) and the films present weak in-plane uniaxial anistropy. The enhancement of the magnetic damping constant due to the capping of Pt is the manifestaction of the generation of spin current in Pt layer. Furthermore, the spin current induces an inverse spin Hall effect (ISHE) in LSM0(20nm)/Pt(5.5nm) system, measured using the FMR in cavity with 9.8 GHz excitation frequency. The linear dependence of ISHE on microwave power validates the mechenism of spin pumping in this bilayer system. [ABSTRACT FROM AUTHOR]