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In this study, the effects of annealing conditions on the magnetic characteristics of multilayered perpendicular magnetic tunnel junctions (pMTJ) of the structures SiNx/Pt/[(Co/Pd).sub.10]/MgO/[(Co/Pt).sub.5]/Pt with various MgO barrier thicknesses were explored. We found that both the fixed and free layers exhibit coercivity growth with increasing annealing temperature. Insertion of a 0.4 nm Mg layer under the MgO barrier layer increases the corecivities further. Magnetoresistance measured by the current-in-plane tunneling (CIPT) method reveals that the insertion of Mg layers on both side of the MgO layer can increase the MR ratio by up to 32%. Index Terms--Co/Pd, Co/Pt, MgO, perpendicular magnetic tunnel junction (pMTJ), tunneling magnetoresistance (TMR).

The sol-gel MgO-Zr[O.sub.2] electrical insulations are coated on Stainless-Steel-304 (SS) tapes by reel-to-reel process for examining electrical properties under various pressure at room temperature and liquid nitrogen temperature for HTS/LTS high field insert coil. The electrical properties are studied as a function of the epoxy type and preparation method.

The developments in magnetic tunnel junctions (MTJs) with their potential impacts on integrated circuits are reported. It is shown that MgO-barrier-based MTJs show a very high Tunnel-magnetoresistance (TMR) ratio and a low J(C) form current-induced magnetization switching (CIMS).

The effect of isovalent chemical substitution of [Eu.sup.3+] into the [Tb.sup.3+] sites on the magnetic and electrical properties of ([Tb.sub.1-x][Eu.sub.x])Mn[O.sub.3] (0 less than equal to x less than equal to 1.0) system is examined. The results have shown that the increase in the Eu content has increased both the tolerance factor and Mn-O bond distance, leading to the reduction in the octahedral distortion and Jahn-Teller (JT) effect.

The surface electronic structure of 1500-angstrom-thick Fe3O4(100) films is investigated by spin0-resolved photoemission spectroscopy with vacuum ultraviolet synchrotron radiation. The top of the valence band is found to be negatively spin polarized, with a value of approximately -50 percent, thus pointing towards the localized nature of the 3d states in the system.

Large tunnel magnetoresistance of approximately 60% in sputter-deposited junctions with plasma oxidized, polycrystalline MgO barriers and Co50Fe50 FM electrodes is demonstrated. These junctions present a resistance-area product approximately two orders of magnitude lower than AlO(sub x) junctions.

Preparation and properties of low symmetry [Mn4O3(O2CPh-R)(sub 4)(dbm)(sub 3)] Single-molecule magnets has been reported. The results confirm the importance of symmetry on the quantum tunneling of magnetization (QTM) rates.

The effect of the support on the adsorbate/metal bond and the effect of the adsorbates on the metal/metal oxide interface are studied. The underlying mechanism for bond strengthening is due to CO-metal and metal-metaloxide bond characteristics.

Magnetic properties of an FeCo/TbFeCo bilayer were investigated by MFM and the anomalous Hall effect. In the case of FeCo(xnm)/TbFeCo(50 nm), FeCo as thin as 2 nm behave as perpendicular magnetization film while large thickness of RE-TM films, such as TbFeCo(100nm) causes the increase of the critical thickness up to 4 nm. The prototype of perpendicular MTJ, p-MTJ, consist of TbFeCo/Fe/MgO/Fe/GdFeCo exhibited high squareness raito of 0.8 having low coercivity of 117 Oe while MgO(100) texture was confirmed in the Fe/MgO/Fe junction prepared on the amorphous GdFeCo layer even though the thickness of MgO is as thin as 3 nm. Index Terms--Magnetic tunneling junction (MTJ), MgO, perpendicular MTJ, p-MRAM, TbFeCo.

Percolated perpendicular FePt-MgO films with a [([Fe.sub.48] [Pt.sub.52])100.sub.-x]-[(MgO).sub.x]/Pt(001)/Cr(002) structure were prepared by conventional dc magnetron sputtering (x = 0 - 6.13). Magnetic measurements demonstrate that the coercivity of the magnetic film drastically increases from 169 to 285 kA/m as the MgO content is increased from 0 to 0.15 vol.%. However, the grain sizes of the FePt phase do not significantly varying upon doping with MgO. MgO does not appear at the grain boundaries of the FePt phase, but is present as crystalline dots that are uniformly precipitated in the FePt matrix. The MFM images revealed that the domain structure transformed from extending to isolate when the MgO dots precipitated into the FePt grains. Consequently, the MgO dots serve as pinning sites of the domain wall and enhance perpendicular coercivity. Percolated perpendicular magnetic recording is thus regarded as a solution to the problem of thermal instability in ultrasmall grains. Index Terms--Coercive force, FePt alloy, percolated meida, perpendicular magnetic recording, precipitation.

Surface diffusion behaviors for Fe and Co adatoms on the MgO (001) surface were investigated using first-principles calculations. The potential energy calculations revealed that Fe and Co adatoms favored the on O site as initial adsorption site. The adsorption energies were calculated to be 1.97 and 0.73 eV for Fe and Co, respectively. Surface diffusion after the adsorption on O site was occurred by passing through the bridge site on the surface and energy barrier for the process was 0.54 eV for both adatoms. The magnetic moment of Co atoms on O site was 3.15 [[micro].sub.B] and the value was significantly reduced at the bridge site as 2.99 [[micro].sub.B], while the corresponding value in vacuum state was 3.50 [[micro].sub.B]. Interestingly, the magnetic moment for Co adatom at the bridge site was increased by 0.08 [[micro].sub.B] compared to the case of adsorbed Co on O site. Spin polarization values for adatoms at the adsorption sites on the substrate were ranged from 82.9% to 100%. Index Terms--Co/MgO(001), Fe/MgO(001), first-principles calculations, magnetic property, surface diffusion.

Current-induced magnetization switching (CIMS) was demonstrated in low resistance magnetic tunnel junctions (MTJs) with thin MgO (001) barrier. The resistance change by CIMS was more than 100%, which is much larger than the previous report in Al-O based MTJs. The switching current density was about 2 x [10.sup.7] A/[cm.sup.2], which was comparable with that reported values in metallic multilayers. Index Terms--Magnesium oxide, magnetic devices, magnetic films, magnetic memories, magnetization reversal, torque, tunneling.

The measurement of DC resistivity (rho) and differential resistance Rd=dV/dI as functions of temperature, magnetic field and current flow in three epitaxial La0.7Ca0.3MnO3 films grown on (001) SrTi3 substrates is discussed. The films were found to be in strain-relaxed, noncoherent and coherent strain states with thickness of 70, 22 and 9 and Curie temperatures of 263, 254 and 220 K respectively.

Reactive sputtering method was used for examining the magnetization hysteresis loop of Fe3O4 thin films deposited on MgO substrates. The saturation moment for in-plane magnetization hysteresis loop was 235 emu/cc and the coercivity was 500 Oe.

The effect of thermo-chemical treatment on the ease of saturation in a magnetic field of epitaxial magnetite (100) thin films grown on MgO (100) substrates is examined. A fully strained state was maintained by the films with the MgO substrate during the treatment in air.

Several studies are conducted to explain the magnetic, as well as the microstructural properties exhibited by the Cu-doped FePt-Zr/MgO multilayer films. The addition of Cu is shown to lead to a significant reduction in the perpendicular magnetic anisotropy of the films.

The magnetic and dielectric characteristics of LuFeMg[O.sub.4] ceramics are examined along with the crystal structure. The dielectric relaxation is suppressed by oxygen annealing, which has shown that oxygen vacancies have played a major role in the dielectric response of LuFeMg[O.sub.4] ceramics.

The evolution of the magnetic transport properties are examined as a function of short annealing time in CoFeB/MgO/CoFeB based magnetic tunnel junctions (MTJs) with a free layer. The magnetoresistance (MR) loops without hysteresis is well fitted by using the superparamagnetism theory, which has shown the formation of superparamagentic particles in the free layer during the high temperature annealing.

The temperature dependent anisotropy of a highly textured epitaxial Pr-Co film with a single orientation of the crystallographic c-axis along MgO[001]is examined by measuring angle dependent hysteresis loops at various temperatures. The studies have shown that the [Pr.sub.15.4][Co.sub.84.6] film has undergone a spin reorientation transition from an easy axis anisotropy to an easy cone anisotropy.

The non-resonant and soft resonant magnetic x-ray scattering technique is employed to explain the impact of annealing on the junction profile of the various different CoFeB/MgO tunnel junctions. The structural quality of the junctions is shown to remain unaffected by the annealing procedure.

Several numerical studies are conducted to explain the impact of the oscillation modes on the properties of the different magnetic tunnel junction nanopillars. An increase in the coherence of the uniform precession mode is shown to lead to the onset of initial line narrowing.

The angular distribution of exchange bias and its size dependence are analyzed in MgO magnetic tunnel junctions with IrMn antiferromagnetic pinning layer. Device size is in the mesoscopic range where the finite number of antiferromagnetic grains has determined the statistical properties of exchange bias.

Several investigations are conducted to study the metallic Mg insertions taking place in rf deposited MgO barrier of magnetic tunnel junctions structure. A tope Mg insertion is shown to lead to lower tunnel magnetoresistance in the structures.

Several measurements based on perpendicular-field magnetoresistance and thermal are conducted for determining the easy-plane anisotropy field of the nanostructured magnetic tunnel junctions. The device to device variations exhibited by the mode frequency shaping of the junctions are also analyzed.

The ferromagnetic resonance study is employed to explain the impact of miscut direction on the magnetic anisotropy exhibited by the different magnetite films that are grown on the vicinal MgO(100) compounds. The compound is shown to exhibit in-plane fourfold, as well as uniaxial anisotropies.

The study employs the infrared magnetorefractive effects to present a comparative analysis of the magnetoresistance observed in the (100) and (111) oriented [Fe.sub.3][O.sub.4] films. Small magnetoresistance is shown to be caused because of the small magnetorefractive effect.

The correlation existing between the various magneto-optical and magnetoresistive properties of the different CoFe-MgO nanocomposite films is analyzed. The correlation is shown to be completely dependent on the spin-dependent and optical conductivity of the films.

Several studies are conducted to explain the interlayer exchange coupling and the current induced magnetization switching taking place in the different magnetic tunnel junctions with MgO wedge barrier. The critical current density of the junctions is shown to highly increase with a decrease in the MgO barrier thickness.

The article explains the design and development of a new Wheatstone bridge sensor, which is shown to be consisting of linear MgO magnetic tunnel junctions.

Several studies are conducted to explain the spin-polarized transport taking place in the Fe/Cr/MgO/Fe magnetic tunnel junctions. The presence of Cr layer is shown to lead to a sharp decrease in the tunnel magnetoresistance of the junctions.

The article presents a new approach, which can be employed for the direct measurement of the spin polarization of [Co.sub.2]FeAl compounds with MgO tunnel barriers.