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The dynamic enhancement of the training effect is reported in an exchange coupled bilayer of soft and hard ferromagnetic materials. The exchange coupled films based on all ferromagnetic materials have used simple magnetometry to provide unique access to the magnetization state of the pinning layer.

Cr-dosed FePt thin films are grown in an ultrahigh vacuum at room temperature and are analyzed by using the surface magneto-optic Kerr effect, scanning electron microscopy and x-ray magnetic circular dichroism. The segregation of Cr during annealing is responsible for the formation of round FePt islands and the separation of the [L1.sub.0] islands and planar A1 phase.

Magnetic properties and structural separation of [La.sub.0.7][([Ca.sub.1-y][Sr.sub.y]).sub.0.3] Mn[O.sub.3] thin films were investigated. The results reveal that the films with 0.3

The importance of the electrocrystallization approach in constructing and precisely controlling the morphology and stoichiometry of Co[[TCNQ].sub.2] (TCNQ = tetracyanoquinodimethane) based materials is presented. The findings show that the electrocrystallization process occurs through two distinctly different, potential-dependent nucleation-growth mechanisms.

The details, compositional characterization, dynamic measurements and observation of the study of the influence of transition metal dopants on the magnetic damping of permalloy, with special focus on the impacts of inhomogeneity on the measurements are mentioned. It is inferred that the damping factor increases linearly with dopant concentration for most of the dopants and the 5d transition metal dopants were the most influenced with a maximum of 7.7 x [10.sup.-3] per atomic percent osmium.

Study presents a complete study of the dispersion formula and dynamic magnetization for magnetostatic waves (MSSWs), in addition to the observation of the mode-conversion enhancement of guided optical waves (GOWs). The results show that the mode-conversion efficiency of the GOWs can be highly improved by optimizing the direction of the bias magnetic field in the plane of the film.

The retention loss behaviors of dot domains and square domains with sizes of 1 and 25 mu[m.sup.2] are observed via a PFM image. This retention loss phenomenon of the domain reversed using an AFM tip is closely related to the shape of the c/c domain wall and the strainpolarization coupling effect of the reversed domain.

A continuum model is presented which accounts for the spatial variation in properties and the long range electrostatic interactions in functionally graded ferroelectric thin films with an emphasis on the dielectric behavior. It is found that the parallel electrode configuration results in a strong temperature dependence of the dielectric constant due to the strong electrostatic interactions between the different layers.

High throughput method is described which is applicable to the development of ferroelectric thin films. The chemical solution deposition techniques containing 90 samples are used to prepare thin film libraries for an automated synthesis route.

The phenomenological Landau-Ginzburg-Devonshire theory is used to numerically investigate the effects of space charges on hysteresis loops and field distributions in ferroelectrics. A method is proposed to help in identifying fully depleted films from temperature dependent capacitance and hysteresis measurements.

Dual-beam high-resolution magneto-optic Kerr effect polarimetry and magnetic force microscopy (MFM) are used to study Barkhausen jumps in thin-film permalloy microstructures. The observations indicate that negative jumps are driven by configurational changes of local domain structure associated with positive jumps that are governed by pinning, exchange and anisotropy energies.

Results from measuring the angular dependence of magnetoresistance (MR) on the [La.sub.0.7][Ca.sub.0.3]Mn[O.sub.3] (LCMO] biepitaxial step junctions (BSJs) obtained by depositing LCMO film onto SrTiO3(100) substrate partially buffered with a layer of anatase TiO2(001) is reported. The magnetudes of anisotropic magnetoresistance (AMR) suggest that the conventional spin-orbit coupling effect, though may explain the in-plane anisotropy is inadequate to account for the perpendicular anisotropy.

The contact resonance of cantilever in scanning probe microscopy is used to amplify small piezoelectric response signals and increase the sensitivity of the detection by many orders of magnitudes. The results are very crucial for studying the ferroelectric and electromechanical properties of nanostructures.

The activities in the growth and advanced characterization of nanoscale ferroelectrics are explored. The atomic force microscope (AFM) is used to study the nanoscale ferroelectric domains, leading to the precise analysis of domain wall creep and roughness in Pb(Zr,Ti)[O.sub.3] thin films.

Chemically synthesized FePt nanocrystals can exhibit room temperature ferromagnetism after being annealed at temperatures above 500 [degrees]C. In thick films composed of FePt nanocrystals, the coercivity can be quite large. However, the coercivity of thin films has been found to decrease significantly with decreasing thickness, to the point that ferromagnetism at room temperature is lost. We studied 12 to 55 nm thick films by using magnetic force microscopy (MFM) under external applied fields. We made smooth films by spin casting 4-nm-diameter FePt nanocrystals and annealing them at 605[degrees] C-630[degrees]C. Thin FePt films showed lower coercivity than thick films. To help interpret the MFM images, we obtained complementary magnetic and structural data by superconducting quantum interference device (SQUID) magnetometry, transmission electron microscopy (TEM), and X-ray diffraction. We conclude that the magnetic properties of these films are strongly affected by nanocrystal aggregation that occurs during annealing. Index Terms--FePt, magnetic force microscopy (MFM), nanocrystal, sintering.

A study is conducted to show that the films grown on MgO (100) substrate remain fully coherent up to much greater thickness than predicted by the FKR model (70 nm) from the strain relaxation studies of epitaxial Fe3O4 thin films grown on MgO (100) substrates. The observed strain relaxation behavior is attributed to the differences in the crystal structure symmetry between MgO and Fe3O4.

A study is conducted to show that the perpendicular injection of a spin-polarized current into a magnetic thin film could induce the domain formation through the spin-transfer effect. The results verify that the spin-transfer effect may induce domain formation in a magnetic thin film while it is also suggested that when the spin-transfer effect is utilized to switch the nanopillar device, the formation may result in the incomplete magnetization switching.

Simulation of very fast surge phenomena in a three-dimensional (3-D) structure requires a method based on Maxwell's equations, such as the finite-difference time-domain (FDTD) method or the method of moments, because circuit-equation-based methods cannot handle the phenomena. This paper uses a method of thin-wire representation of the vertical conductor system for the FDTD method which is suitable for the 3-D surge simulation. The thin-wire representation is indispensable to simulate electromagnetic surges on wires or steel frames in which the radius is smaller than a discretized space step used in the FDTD simulation. In this paper, a general surge analysis program named the virtual surge test lab based on the Maxwell's equations formulated by the FDTD method, is used to simulate the surge phenomena of a vertical conductor, including the effects of horizontal wave incidence and vertical wave incidence. Experimental results on the reduced scale model have been presented in order to compare among the simulation results by the FDTD method and the results using numerical electromagnetic code based on the MoM. Index Terms--Finite-difference time-domain (FDTD) method, numerical electromagnetic code (NEC-2), surge analysis, thin wire, vertical conductor.

Ferroelectric films of BaSrTiO3 (BST) are identified as a potential alternative to silicon dioxide in the silicon-based microelectronics industry owing to their very high dielectric constant. The distribution of space charge and polarization in BST ceramics is studied at room temperature with the laser induced pressure pulse method.

Transmission electron microscopy (TEM) is used to study magnetization processes in four high moment COFe films. While all films were of similar total thickness, 50 nm the differences between them were the inclusion or otherwise of a seed layer and the introduction of nonmagnetic spacers to form laminated films.

The microstructure of the SmCo5 thin films sputter deposited on Cu underlayers is investigated to explain the high coercivity [H.sub.c]. Energy filtered elemental map and energy dispersive x-ray spectroscopy line analysis showed that Cu diffused into the SmCo5 layer to form a Sm(Co,Cu)5 solid solution.

A heterojunction is fabricated by depositing La0.67Ca0.33MnO3 film on electron doped silicon wafer with a buffer layer of natural SiO2. The current-voltage measurement shows that it is a diode with a good rectifying property in a wide temperature range.

The magnetic coupling between two continuous Fe layers of fixed thickness separated by a granular Fe-SiO2 spacer by varying thickness and compositions is studied. The magnetic response with dc magnetization and ferromagnetic resonance (FMR) is analyzed.

The ferroelectric and magnetic properties of multiferric epitaxial BiFe[O.sub.3] thin films are investigated in the framework of a general Landau free energy function. The film thickness dependence of epitaxial strains due to relaxation by misfit dislocations during film deposition is incorporated into the model by using an effective substrate lattice parameter, thereby explaining the thickness dependence of ferroelectric and magnetic properties in BiFe[O.sub.3] epitaxial thin films.

This paper presents an innovative test procedure for the prediction of the shielding effectiveness of small sample materials, consisting of a dielectric substrate coated with thin conducting film, in a wide frequency range up to 8 GHz. The proposed technique overcomes the limitations of the ASTM D4935 test method concerning the upper operating frequency and the required minimum specimen dimensions. A new high-order equivalent circuit model of the test fixture is developed. A correction factor is applied to the measured insertion loss to eliminate both the resonance peak below cutoff appearing in the high-frequency range and the low-frequency errors due to the weak capacitive coupling between the flanges of the coaxial cell. The accurate prediction of the shielding effectiveness of the test material against a plane wave is then derived from the insertion loss measurements. Index Terms--ASTM D4935 test method, high-order equivalent circuit, shielding effectiveness (SE), thin films.

For integrated radio-frequency applications, tunable magnetic inductors are expected. A tunable magnetic inductor, based on magnetoimpedance effect, is presented in this paper. The proposed inductor is constructed with a magnetic inductor body, wound by an insulated coil, inducing a longitudinal dc bias magnetic field when a dc control current is flowing through. Formed by a conductive core coated by a high-permeability magnetic layer, the magnetic inductor body can be realized by either a thin-film structure or a composite wire. The reluctance models for both thin-film and composite wire structures are studied. A prototype tunable magnetic inductor, using a composite wire element, has been characterized. The results show that by varying the dc control current, the inductance L of the magnetic inductor can be tuned. The tunable range depends on the frequency of the current flowing through the inductor. A relative variation of inductance [DELTA]L/[L.sub.o], up to 18% at low frequency (around 5 MHz), is achieved by applying a bias current of magnitude merely up to 15 mA. The quality factor varies from 5 to 17 in the measured frequency range. The proposed tunable inductor may be further optimized for high-frequency applications and has the potential to be realized in micro-electromechanical systems technology. Index Terms--Inductors, magnetic films, magnetoimpedance, tunable circuits and devices.

The magnetoresistance (MR) in Fe/Cr magnetic multilayers (MML) has been measured under high pressure up to 2.5 GPa. It is found that the spin-dependent scattering plays an important role in the pressure dependence of MR ratio. In the present work, for [[Fe(20 [Angstrom])/Cr(10 [Angstrom])].sub.20] MML with antiferromagnetic (AF) state, the pressure coefficient of saturation field [H.sub.s] is (1/[H.sub.s])([partial derivative][H.sub.s]/P[partial derivative]) = 3.3 x [10.sup.-2] [GPa.sup.-1] between 0.1 and 2.5 GPa. We found that the (1/|J|)([partial derivative]|J|/[partial derivative]P) for AF-Fe/Cr MML with polycrystalline structure is opposite in sign to that with epitaxial one. For [Fe(20 [[Angstrom])/Cr(22 [Angstrom])].sub.20] MML with ferromagnetic (F) state, anisotropic magnetoresistance (AMR) decreases with increasing pressure. It is suggested that the anisotropy constant decreases with weakening spin-orbit interaction at high pressure. At high field, the AMR is easily suppressed by applying pressure while the giant magnetoresistance around [H.sub.s] increases slightly with increasing pressure for polycrystalline Fe/Cr MML. Index Terms--Giant magnetoresistance, multilayers, pressure effects, superlattices, thin films.

We report the magnetic behaviors of [Fe.sub.3][O.sub.4] thin films grown by zero field growth (ZFG) and field growth (FG) techniques during the sputtering process. In FG conditions, an in situ 300 Oe field during growth is applied to a substrate, inducing an easy axis of magnetization. Structural observations obtained by high-resolution transmission electron microscopy measurements clearly depicted a significant reduction of the grain boundaries and voids in the [Fe.sub.3][O.sub.4] films grown under FG conditions, thus explaining the saturated magnetization of the [Fe.sub.3][O.sub.4] films at about 0.01 T. This behavior was expected due to a remarkable reduction of the antiferromagnetic exchange couplings between grains for FG conditions. In addition, the zero-field-cooled magnetization of the ZFG samples showed an abrupt change at about 285 K, confirming the existence of defects or other phases in the ZFG films. Index Terms--Magnetic domain, magnetic field effect, magnetic hysterisis, magnetic materials.

The in-plane magnetic anisotropy of (001) oriented InMnAs epitaxial films grown on InAs and GaSb are measured by magnetometry and the longitudinal magneto-optic Kerr effect. The isotropic behavior is attributed to three-dimensional island growth of films grown on GaSb that eliminates long-range order.

A complex transverse alternating-current (ac) suspectibility [X.sub.T] technique based on magneto-optical detection is developed with sufficient sensitivity for thin film recording media. The technique is used to measure the dispersions in grain size and anisotropy field in perpendicular magnetic recording media.

The structure, morphology, composition, magnetism, and magneto-optical (MO) response of FePd films sputter deposited at different temperatures on a monocrystalline V(001) buffer layer is studied. It is observed that the perpendicular magnetic anisotropy (PMA) could be ascribed to the V interdiffusion and the formation of a FeV alloy, being the global sample saturation magnetization also reduced.

A dynamic model of electromagnetic devices constructed with magnetostrictive thin film is developed to study the dynamic characteristics of the system. In the developed model, the inductance is considered as current and geometry dependent so as to represent the magneto-elastic property of the magnetostrictive thin film. Such an inductance is obtained from coupled magnetoelastic field solutions. Element-free Galerkin method (EFGM) is adopted in numerical field analysis so as to describe the magnetostrictive thin film; the [DELTA]E effect is considered to improve the material property modeling. The developed simulation model is examined through comparing the simulated current-voltage characteristic with the measured one. Index Terms--Dynamic model, element-free Galerkin method (EFGM), magnetostrictive thin film, magneto-elastic coupling.

The multilevel fast multipole algorithm (MLFMA) is an established way to accelerate the solution of the integral equations governing scattering of electromagnetic waves. Another way is to use high-order methods, of which the locally corrected Nystrom (LCN) method is, perhaps, the best; it has been applied to metallic scatterers up to order 10. In this paper, the technique (MLFMA + LCN) is extended to handle mixed conducting/dielectric bodies. Results for coated circular and square cylinders, using orders up to 8, demonstrate the efficiency of the method. Index Terms--Boundary element methods, dielectric films, electromagnetic scattering, multilevel systems.

The structural and magnetic properties of Nd(0.7)Ce(0.3)MnO3 (NCeMO) epitaxial thin films lacking Ce-rich impurities is reported in order to investigate the effect of ionic radius of the A site cation on the microstructures and magnetic properties in comparision with (La, Ce)MnO3 (LCeMO) systems. The results by high resolution transmission electron microscopy confirmed the absence of Ce-rich impurities in NCeMO films.

A theoretical study is performed to rationalize the strong evolution of (001) texture during postannealing of deposited Fe50Pt50 thin films on amorphorus substrates, by comparing calculated strain energies of several crystals with different orientations under presumed strain conditions. It is proposed that the occurrence of anisotropic strain due to ordering transformations should be considered as a key factor that affects the texture evolution and that enhanced ordering and recrystallization kinetics is necessary to maximize the strain effect.

The magnetization reversal of Permalloy disks with a small circular void either concentric or decentered is studied. For the disks with the concentric void, no preferential rotation is observed and in the case of decentered void, the sense of rotation of all probed disks is deterministically controlled by appropriately choosing the direction of the externally applied field and the void position with respect to the disk center.

The magneto-optical properties (MO) of compressively strained La(sub 0.7)Sr(sub 0.3)MnO(sub 3) (LSMO) thin films epitaxially grown on a LaAlO(sub 3) substrate are described. The magnetic force microscope show the stripe magnetic domains, characteristic of the films with the perpendicular magnetic anisotropy (PMA), several charge-transfer-type MO spectra are observed above 2eV and their peak position and intensity are found to be sensitive to the film thickness.

The structure and properties of FeTaN thin films deposited on the plastic substrate by rf magnetron sputtering were investigated. High values were obtained for complex permeability and ferromagnetic resonance frequency indicating that the nature of the substrate has an important effect on the structure and soft magnetic properties of the deposited films.

We deposited face-centered cubic (FCC) Co films on glass substrates by sputtering. From Auger-depth profile analysis, we found that there is one CoO layer, about 13 [Angstrom] thick, lying on the top surface of the Co film, and another CoO layer, about 37 [Angstrom] thick, lying within the Co/glass interface. At room temperature, the thin CoO film is supposed to be paramagnetic. However, because of the proximity effect between CoO and Co, the CoO layer may become ferromagnetic, with saturation magnetization Mo. By fitting the saturation magnetization ([M.sub.s]) data of the whole Co/CoO film as a function of (1/[t.sub.f]), where [t.sub.f] is the Co thickness, we can prove that the last conjecture is correct, and the [M.sub.o] of the CoO layer is indeed not zero. Both the [t.sub.f] dependence of the magnetostriction constant ([[lambda].sub.s]) and the [t.sub.f] dependence of the coercive field ([H.sub.c]) show a two-region characteristic. The dividing line for the former quantity is at [t.sub.f] = 88 [Angstrom], and for the latter it is at [t.sub.f] = 120 [Angstrom]. When crossing such a dividing line, there is a discontinuous jump in [[lambda].sub.s] (or [H.sub.c]). These phenomena occur because the lattice-strain and magnetoelastic effects within the CoO layer dominate the ([[lambda].sub.s]) and the [H.sub.c] behavior in ultra-thin ([t.sub.f] < 88 [Angstrom]) Co films. In this region, the roughness-to-thickness ratio ([S.sub.q]/[t.sub.f]) may also affect ([[lambda].sub.s]). Finally, there seems to be no connection between the grain size (D) and [H.sub.c]. Index Terms--Co film, magnetostriction, proximity effect.

X-ray transmission microscopy technique allows for an element-specific imaging of magnetic domain structures in thin films and nanopatterned elements. Recording the images in varying applied magnetic fields is of particular importance to obtain detailed insight into fundamental mechanisms of magnetization reversal processes.

The ability to model features that are small relative to the cell size is often important in electromagnetic simulations. In this paper, the focus is on modeling of thin material sheets and coatings in the finite-element time-domain method. The proposed method is based on degenerated prism elements, so-called shell elements. For a dielectric sheet the thickness is assumed small compared to the wavelength for all frequencies of interest. An important characteristic of the method is that it takes the discontinuity of the normal electric field component at a dielectric interface into account. The accuracy of the method is demonstrated for three different scattering cases. Comparisons are made with analytical data and results obtained on grids for which the thickness of the sheets is resolved. Good agreement is observed in all cases. Index Terms--Finite element methods (FEMs), subcell models, time-domain (TD) methods.

An investigation was performed on the correlation of electrical properties with magnetic properties for As(super +)-implanted p-(Zn0.93Mn0.07)O thin films. It was clearly observed that the electrical mobility at the cryogenic temperature region is increased with decreasing temperatures for electrical transport measurements.

Self-heating due to write currents is a critical concern in thin-film magnetic recording heads; the reliability of the head-media interface and magnetoresistive sensors can be degraded by excessive temperature rise during writing operations. A combined experimental and theoretical study shows that the magnetic saturation of yoke structures and the heat transfer across the air bearing strongly influence the magnitude and spatial distribution of the temperature rise. This paper describes three-dimensional numerical heat transfer simulations that can accurately model self-heating as a function of the amplitude and frequency of write current pulses. Index Terms--Air bearing, eddy current, magnetic heads, self-heating, yoke saturation.

We have studied magnetization reversal behaviors of diamond-shaped NiFe nanofilm elements with different length-to-width ratios (LWRs) between long and short diagonals by micromagnetic simulation. The results show that the reversal process of the diamondshaped element strongly depends on the LWR. If the LWR is smaller than 2, the reversal starts at the element edge, but it starts from the center of the element with larger LWR. With a bias field and when the LWR is larger than 2, all the elements experience a similar reversal process, which is simple and unique. In addition, the switching field becomes stable and nearly constant. These results suggest that the diamond-shaped NiFe nanofilm element can be potentially used in magnetic random access memory. Index Terms--Diamond-shaped elements, magnetization reversal, micromagnetic simulation, NiFe.

The magnetostriction of magnetically diluted (Lu(sub 3-x)Bi(sub x)Fe(sub 5-y)Ga(sub y)O12) (BiLuIG) thin films grown by epitaxial deposition on (111)-oriented gallium gadolinium garnet substrates were optically studied. The real-time optical observations of stripe magnetic domains and their evolution under external applied magnetic fields and applied stresses are reported.

Large room-temperature magnetoresistive ratio (MR) for Bi thin ribbons fabricated by a straightforward and convenient method of rapid solidification, melt spinning are reported. The results indicate that the rapid solidification process provides good-quality-textured Bi samples with a low density of crystalline defects that might be suitable for magnetoelectronic application.

Multilayers of 200-nm thick Co-free or Co-doped Nd-Fe-B with 10-nm thick Ta were prepared by sputtering on heated glass substrates and investigated into the microstructure, texture and hard magnet properties. The perpendicularly textured [Nd.sub.2][Fe.sub.14]B grains evolved in the multilayers with sizes neatly controlled by the thickness of the unit layer. Co was found to dissolve in the [Nd.sub.2][Fe.sub.14]B grains, resulting in the enhanced c-axis texture possibly due to the modulated surface energy of the [Nd.sub.2][Fe.sub.14]B phase. It was also found that Co boosts the crystallization and grain growth of the [Nd.sub.2][Fe.sub.14]B phase, rapidly leading to the relatively stable multilayered structure where the dimension of the [Nd.sub.2][Fe.sub.14]B grains is exactly defined by the thickness of the unit layer. Such effect of Co suppresses the local variation of the microstructure and minimizes the deterioration of the permanent magnet properties of the multilayer with an increased thickness of 10-[micro]m. Index Terms--Permanent magnets, perpendicular magnetic anisotropy, sputtering, thin films.

Domain-wall structures and magnetization ripple spectra in permalloy films with widely varying values of anisotropy field and thickness is studied. In accord with expectations, the mean ripple wavelength and magnitude of the ripple decreased with increasing anisotropy field.

The effect of the density of ion-induced electronic excitations on the nucleation of Fe particles in a silicon-based gel and on the magnetic ordering in SiO2:Fe composites with a volume fraction of metal of a few percent derived from the same gel is examined. Irradiation-induced changes in the magnetic anisotropy of composite films depend on the order of magnitude of electronic energy loss S(sub e).